diff --git a/exec/bootstrap.php b/exec/bootstrap.php
index c88fb1a..f4ea95b 100644
--- a/exec/bootstrap.php
+++ b/exec/bootstrap.php
@@ -12,6 +12,7 @@ define('PLUGIN_EXEC_DIR', __DIR__);
 
 foreach ([
     'Settings.php',
+    'BackendRuntimeConfig.php',
     'Http.php',
     'DirectAdminUser.php',
     'Lang.php',
@@ -30,6 +31,7 @@ require_once PLUGIN_EXEC_DIR . '/handlers/_form_helpers.php';
 
 try {
     $settings = Settings::load(Settings::EXTERNAL_SETTINGS);
+    BackendRuntimeConfig::sync($settings, PLUGIN_ROOT . '/scripts/backend.sh', Settings::CONFIG_DIR . '/backend-state.json');
     $user = DirectAdminUser::fromEnvironment($settings);
     $lang = Lang::load($user->language(), $settings);
     if (!$user->hasPluginAccess($settings)) {
diff --git a/exec/handlers/_form_helpers.php b/exec/handlers/_form_helpers.php
index 5a69f38..8b1fadd 100644
--- a/exec/handlers/_form_helpers.php
+++ b/exec/handlers/_form_helpers.php
@@ -16,14 +16,12 @@ function render_rule_form(AppContext $ctx, string $mode, ?array $rule): string
     $hiddenId = $isUpdate ? '<input type="hidden" name="id" value="' . AppContext::e($id) . '">' : '';
 
     return '<form method="post" action="' . AppContext::e($action) . '">' . $csrf . $hiddenId .
-        '<div class="grid grid-2"><div class="panel"><h3>Treść odpowiedzi</h3><div class="row"><div><label>' . AppContext::e($ctx->t('Subject')) . '</label><input type="text" name="subject" value="' . AppContext::e((string)$subject) . '"></div>' .
+        '<div class="panel"><h3>' . AppContext::e($ctx->t('Response content')) . '</h3><div class="row"><div><label>' . AppContext::e($ctx->t('Subject')) . '</label><input type="text" name="subject" value="' . AppContext::e((string)$subject) . '"></div>' .
         '<div><label>' . AppContext::e($ctx->t('Status')) . '</label><label class="br-time-item"><input type="checkbox" name="enabled" value="1" ' . ($enabled ? 'checked' : '') . '> ' . AppContext::e($ctx->t('Enabled')) . '</label></div></div>' .
         '<label>' . AppContext::e($ctx->t('Message body')) . '</label><textarea name="body">' . AppContext::e((string)$body) . '</textarea></div>' .
-        '<div class="panel"><h3>Podsumowanie</h3><div class="summary-card"><div class="kv"><strong>Zakres</strong><span>' . AppContext::e($ctx->t('All valid POP/IMAP mailboxes in this account')) . '</span></div>' .
-        '<div class="kv"><strong>Start</strong><span>' . AppContext::e($startValue) . '</span></div><div class="kv"><strong>Koniec</strong><span>' . AppContext::e($endValue) . '</span></div></div>' .
-        '<div class="actions"><button class="primary" type="submit">' . AppContext::e($ctx->t($isUpdate ? 'Save changes' : 'Save autoresponder')) . '</button><a class="btn" href="' . AppContext::e($ctx->url('index.html')) . '">' . AppContext::e($ctx->t('Cancel')) . '</a></div></div></div>' .
-        render_calendar_picker('start_value', 'Data rozpoczęcia', $startValue) .
-        render_calendar_picker('end_value', 'Data zakończenia', $endValue) .
+        render_calendar_picker($ctx, 'start_value', $ctx->t('Start date'), $startValue) .
+        render_calendar_picker($ctx, 'end_value', $ctx->t('End date'), $endValue) .
+        '<div class="panel"><div class="actions"><button class="primary" type="submit">' . AppContext::e($ctx->t($isUpdate ? 'Save changes' : 'Save autoresponder')) . '</button><a class="btn" href="' . AppContext::e($ctx->url('index.html')) . '">' . AppContext::e($ctx->t('Cancel')) . '</a></div></div>' .
         '</form>';
 }
 
@@ -32,18 +30,28 @@ function normalize_rule_post(array $post): array
 {
     foreach (['start_value', 'end_value'] as $key) {
         $date = trim((string)($post[$key . '_date'] ?? ''));
-        $hour = trim((string)($post[$key . '_hour'] ?? ''));
-        if ($date !== '' && preg_match('/^[0-9]{2}$/', $hour)) {
-            $post[$key] = $date . 'T' . $hour . ':00';
+        $time = trim((string)($post[$key . '_time'] ?? ''));
+        $period = trim((string)($post[$key . '_period'] ?? ''));
+        if ($date !== '' && preg_match('/^[0-9]{2}:[0-9]{2}$/', $time)) {
+            $post[$key] = $date . 'T' . $time;
+        } elseif ($date !== '' && preg_match('/^(morning|afternoon|evening)$/', $period)) {
+            $post[$key] = $date . '|' . $period;
         }
     }
     return $post;
 }
 
-function render_calendar_picker(string $name, string $title, string $value): string
+function render_calendar_picker(AppContext $ctx, string $name, string $title, string $value): string
 {
+    $mode = $ctx->settings->scheduleMode();
     $selectedDate = substr($value, 0, 10);
-    $selectedHour = substr($value, 11, 2) ?: '09';
+    $selectedTime = '09:00';
+    $selectedPeriod = 'morning';
+    if ($mode === 'exact_hour' && preg_match('/T([0-9]{2}:[0-9]{2})$/', $value, $m)) {
+        $selectedTime = $m[1];
+    } elseif ($mode === 'directadmin_period' && preg_match('/\|(morning|afternoon|evening)$/', $value, $m)) {
+        $selectedPeriod = $m[1];
+    }
     $days = '';
     for ($week = 0, $day = 1; $week < 4; $week++) {
         $days .= '<tr>';
@@ -54,14 +62,19 @@ function render_calendar_picker(string $name, string $title, string $value): str
         }
         $days .= '</tr>';
     }
-    $hours = '';
-    foreach (['08', '09', '10', '11', '12', '13', '14', '15', '16', '17', '18'] as $hour) {
-        $hours .= '<label class="br-time-item"><input type="radio" name="' . AppContext::e($name . '_hour') . '" value="' . $hour . '" ' . ($hour === $selectedHour ? 'checked' : '') . '> ' . $hour . ':00</label>';
+    if ($mode === 'exact_hour') {
+        $timeControl = '<label>' . AppContext::e($ctx->t('Time')) . '</label><input type="time" name="' . AppContext::e($name . '_time') . '" value="' . AppContext::e($selectedTime) . '" step="60">';
+    } else {
+        $timeControl = '<label>' . AppContext::e($ctx->t('Time of day')) . '</label><select name="' . AppContext::e($name . '_period') . '">' .
+            '<option value="morning"' . ($selectedPeriod === 'morning' ? ' selected' : '') . '>' . AppContext::e($ctx->t('Morning')) . '</option>' .
+            '<option value="afternoon"' . ($selectedPeriod === 'afternoon' ? ' selected' : '') . '>' . AppContext::e($ctx->t('Afternoon')) . '</option>' .
+            '<option value="evening"' . ($selectedPeriod === 'evening' ? ' selected' : '') . '>' . AppContext::e($ctx->t('Evening')) . '</option>' .
+            '</select>';
     }
     return '<div class="panel"><h3>' . AppContext::e($title) . '</h3><div class="br-restore-layout"><div class="br-restore-calendar"><h4>' . AppContext::e($title) . '</h4><div class="br-month-nav"><button type="button" class="br-month-btn">&lsaquo;</button><span class="br-month-label">Czerwiec 2026</span><button type="button" class="br-month-btn">&rsaquo;</button></div>' .
         '<table class="br-calendar-grid"><thead><tr><th>Pn</th><th>Wt</th><th>Śr</th><th>Cz</th><th>Pt</th><th>Sb</th><th>Nd</th></tr></thead><tbody>' . $days . '</tbody></table>' .
         '<div class="br-date-label" id="' . AppContext::e($name . '_label') . '">Wybrano: ' . AppContext::e($selectedDate) . '</div><input type="hidden" id="' . AppContext::e($name . '_date') . '" name="' . AppContext::e($name . '_date') . '" value="' . AppContext::e($selectedDate) . '"></div>' .
-        '<div class="br-restore-calendar"><h4>Godzina</h4><div class="br-time-picker"><div class="br-time-title">Wybierz godzinę</div><div class="br-time-list">' . $hours . '</div></div></div></div>' .
+        '<div class="br-restore-calendar"><h4>' . AppContext::e($ctx->t('Time')) . '</h4>' . $timeControl . '</div></div>' .
         '<input type="hidden" name="' . AppContext::e($name) . '" value="' . AppContext::e($value) . '"></div>';
 }
 
diff --git a/exec/handlers/delete.php b/exec/handlers/delete.php
index d052cb5..a50ed1e 100644
--- a/exec/handlers/delete.php
+++ b/exec/handlers/delete.php
@@ -5,7 +5,7 @@ return static function (AppContext $ctx): void {
     $id = Http::isPost() ? $ctx->post('id') : $ctx->query('id');
     $rule = $ctx->rules->find($ctx->daUser->username(), $id);
     if ($rule === null) {
-        $ctx->render('Confirm deletion', '<div class="alert alert-err">Rule not found</div>');
+        $ctx->render('Confirm deletion', '<div class="alert alert-err">' . AppContext::e($ctx->t('Rule not found')) . '</div>');
         return;
     }
     if (Http::isPost()) {
@@ -20,7 +20,7 @@ return static function (AppContext $ctx): void {
         }
     }
     $body = '<div class="grid grid-2"><div class="panel"><h3>' . AppContext::e($ctx->t('Preview autoresponder')) . '</h3>' . render_preview_box($rule) . '</div>' .
-        '<div class="panel"><h3>' . AppContext::e($ctx->t('Confirm deletion')) . '</h3><div class="alert alert-err">Usunięcie reguły wyłączy odpowiedź automatyczną utworzoną przez tę regułę dla objętych skrzynek.</div>' .
+        '<div class="panel"><h3>' . AppContext::e($ctx->t('Confirm deletion')) . '</h3><div class="alert alert-err">' . AppContext::e($ctx->t('Deleting this rule will disable the automatic reply created by this rule for covered mailboxes.')) . '</div>' .
         '<form method="post" action="' . AppContext::e($ctx->url('delete.html')) . '">' . $ctx->csrfField('delete:' . $id) . '<input type="hidden" name="id" value="' . AppContext::e($id) . '">' .
         '<div class="actions"><button class="danger-fill" type="submit">' . AppContext::e($ctx->t('Delete autoresponder')) . '</button><a class="btn" href="' . AppContext::e($ctx->url('index.html')) . '">' . AppContext::e($ctx->t('Do not delete')) . '</a></div></form></div></div>';
     $ctx->render('Confirm deletion', $body);
diff --git a/exec/handlers/index.php b/exec/handlers/index.php
index ad1a9b0..75c2b35 100644
--- a/exec/handlers/index.php
+++ b/exec/handlers/index.php
@@ -24,8 +24,8 @@ return static function (AppContext $ctx): void {
         $enabled = !empty($rule['enabled']);
         $rows .= '<tr><td><span class="badge ' . ($enabled ? 'ok' : 'off') . '">' . AppContext::e($ctx->t($enabled ? 'Enabled' : 'Disabled')) . '</span></td>';
         $rows .= '<td>' . AppContext::e((string)$rule['subject']) . '<br><span class="muted">' . date('Y-m-d H:i', (int)($rule['updated_at'] ?? time())) . '</span></td>';
-        $rows .= '<td>' . AppContext::e(date('Y-m-d H:i', (int)$rule['start_ts'])) . '<br><span class="muted">do ' . AppContext::e(date('Y-m-d H:i', (int)$rule['end_ts'])) . '</span></td>';
-        $rows .= '<td>' . AppContext::e($rule['dynamic_scope'] ? 'Dynamiczny' : 'Snapshot') . '</td><td><span class="table-actions">';
+        $rows .= '<td>' . AppContext::e(date('Y-m-d H:i', (int)$rule['start_ts'])) . '<br><span class="muted">' . AppContext::e($ctx->t('To')) . ' ' . AppContext::e(date('Y-m-d H:i', (int)$rule['end_ts'])) . '</span></td>';
+        $rows .= '<td>' . AppContext::e($ctx->t($rule['dynamic_scope'] ? 'Dynamic' : 'Snapshot')) . '</td><td><span class="table-actions">';
         $rows .= '<a class="btn" href="' . AppContext::e($ctx->url('update.html', ['id' => $id])) . '">' . AppContext::e($ctx->t('Edit')) . '</a>';
         $rows .= '<a class="btn" href="' . AppContext::e($ctx->url('preview.html', ['id' => $id])) . '">' . AppContext::e($ctx->t('Preview')) . '</a>';
         $rows .= '<form method="post" action="' . AppContext::e($ctx->url('toggle.html')) . '">' . $ctx->csrfField('toggle:' . $id) . '<input type="hidden" name="id" value="' . AppContext::e($id) . '"><button>' . AppContext::e($ctx->t($enabled ? 'Disable' : 'Enable')) . '</button></form>';
@@ -35,6 +35,6 @@ return static function (AppContext $ctx): void {
 
     $body = '<div class="panel"><div class="panel-head"><div><h3>' . AppContext::e($ctx->t('Global autoresponders')) . '</h3><p class="muted">' . AppContext::e($ctx->t('All valid POP/IMAP mailboxes in this account')) . '</p></div>' .
         '<a class="btn amber" href="' . AppContext::e($ctx->url('create.html')) . '">' . AppContext::e($ctx->t('Add autoresponder')) . '</a></div>' .
-        '<table><thead><tr><th>Status</th><th>' . AppContext::e($ctx->t('Subject')) . '</th><th>Okres wysyłki</th><th>Zakres</th><th>Akcje</th></tr></thead><tbody>' . $rows . '</tbody></table></div>';
+        '<table><thead><tr><th>' . AppContext::e($ctx->t('Status')) . '</th><th>' . AppContext::e($ctx->t('Subject')) . '</th><th>' . AppContext::e($ctx->t('Sending period')) . '</th><th>' . AppContext::e($ctx->t('Scope')) . '</th><th>' . AppContext::e($ctx->t('Actions')) . '</th></tr></thead><tbody>' . $rows . '</tbody></table></div>';
     $ctx->render('Global autoresponders', $body, $ok);
 };
diff --git a/exec/handlers/preview.php b/exec/handlers/preview.php
index 2f43ddb..da53271 100644
--- a/exec/handlers/preview.php
+++ b/exec/handlers/preview.php
@@ -5,12 +5,12 @@ return static function (AppContext $ctx): void {
     $id = $ctx->query('id');
     $rule = $ctx->rules->find($ctx->daUser->username(), $id);
     if ($rule === null) {
-        $ctx->render('Preview autoresponder', '<div class="alert alert-err">Rule not found</div>');
+        $ctx->render('Preview autoresponder', '<div class="alert alert-err">' . AppContext::e($ctx->t('Rule not found')) . '</div>');
         return;
     }
     $body = '<div class="grid grid-2"><div class="panel"><h3>' . AppContext::e($ctx->t('Preview autoresponder')) . '</h3>' . render_preview_box($rule) . '</div>' .
-        '<div class="panel"><h3>Szczegóły reguły</h3><div class="summary-card"><div class="kv"><strong>Status</strong><span>' . AppContext::e($ctx->t(!empty($rule['enabled']) ? 'Enabled' : 'Disabled')) . '</span></div>' .
-        '<div class="kv"><strong>Okres</strong><span>' . AppContext::e(date('Y-m-d H:i', (int)$rule['start_ts']) . ' - ' . date('Y-m-d H:i', (int)$rule['end_ts'])) . '</span></div></div>' .
-        '<div class="actions"><a class="btn" href="' . AppContext::e($ctx->url('update.html', ['id' => $id])) . '">' . AppContext::e($ctx->t('Edit')) . '</a><a class="btn danger" href="' . AppContext::e($ctx->url('delete.html', ['id' => $id])) . '">' . AppContext::e($ctx->t('Delete')) . '</a><a class="btn" href="' . AppContext::e($ctx->url('index.html')) . '">Powrót</a></div></div></div>';
+        '<div class="panel"><h3>' . AppContext::e($ctx->t('Rule details')) . '</h3><div class="summary-card"><div class="kv"><strong>' . AppContext::e($ctx->t('Status')) . '</strong><span>' . AppContext::e($ctx->t(!empty($rule['enabled']) ? 'Enabled' : 'Disabled')) . '</span></div>' .
+        '<div class="kv"><strong>' . AppContext::e($ctx->t('Sending period')) . '</strong><span>' . AppContext::e(date('Y-m-d H:i', (int)$rule['start_ts']) . ' - ' . date('Y-m-d H:i', (int)$rule['end_ts'])) . '</span></div></div>' .
+        '<div class="actions"><a class="btn" href="' . AppContext::e($ctx->url('update.html', ['id' => $id])) . '">' . AppContext::e($ctx->t('Edit')) . '</a><a class="btn danger" href="' . AppContext::e($ctx->url('delete.html', ['id' => $id])) . '">' . AppContext::e($ctx->t('Delete')) . '</a><a class="btn" href="' . AppContext::e($ctx->url('index.html')) . '">' . AppContext::e($ctx->t('Back')) . '</a></div></div></div>';
     $ctx->render('Preview autoresponder', $body);
 };
diff --git a/exec/handlers/toggle.php b/exec/handlers/toggle.php
index df25faf..d758ed1 100644
--- a/exec/handlers/toggle.php
+++ b/exec/handlers/toggle.php
@@ -7,7 +7,7 @@ return static function (AppContext $ctx): void {
     $ctx->requireCsrf('toggle:' . $id);
     $rule = $ctx->rules->find($ctx->daUser->username(), $id);
     if ($rule === null) {
-        throw new RuntimeException('Rule not found');
+        throw new RuntimeException($ctx->t('Rule not found'));
     }
     $ctx->rules->update($ctx->daUser->username(), $id, ['enabled' => empty($rule['enabled'])]);
     Http::redirect($ctx->url('index.html', ['status' => 'toggled']));
diff --git a/exec/handlers/update.php b/exec/handlers/update.php
index 8f580f0..114f6b5 100644
--- a/exec/handlers/update.php
+++ b/exec/handlers/update.php
@@ -5,7 +5,7 @@ return static function (AppContext $ctx): void {
     $id = Http::isPost() ? $ctx->post('id') : $ctx->query('id');
     $rule = $ctx->rules->find($ctx->daUser->username(), $id);
     if ($rule === null) {
-        $ctx->render('Edit autoresponder', '<div class="alert alert-err">Rule not found</div>');
+        $ctx->render('Edit autoresponder', '<div class="alert alert-err">' . AppContext::e($ctx->t('Rule not found')) . '</div>');
         return;
     }
     $errors = [];
diff --git a/exec/lib/AppContext.php b/exec/lib/AppContext.php
index e1ee114..2ef86bb 100644
--- a/exec/lib/AppContext.php
+++ b/exec/lib/AppContext.php
@@ -108,14 +108,16 @@ final class AppContext
 
     private function scripts(): string
     {
-        return <<<'JS'
+        $selectedLabel = json_encode($this->t('Selected'), JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_AMP | JSON_HEX_QUOT);
+        return <<<JS
 (function () {
+  var selectedLabel = {$selectedLabel};
   document.querySelectorAll('[data-date-value]').forEach(function (btn) {
     btn.addEventListener('click', function () {
       var target = document.getElementById(btn.getAttribute('data-date-target'));
       var label = document.getElementById(btn.getAttribute('data-date-label'));
       if (target) { target.value = btn.getAttribute('data-date-value') || ''; }
-      if (label) { label.textContent = 'Wybrano: ' + (btn.getAttribute('data-date-value') || ''); }
+      if (label) { label.textContent = selectedLabel + ': ' + (btn.getAttribute('data-date-value') || ''); }
       btn.closest('.br-restore-calendar').querySelectorAll('.br-cal-day').forEach(function (d) { d.classList.remove('is-selected'); });
       btn.classList.add('is-selected');
     });
diff --git a/exec/lib/BackendRuntimeConfig.php b/exec/lib/BackendRuntimeConfig.php
new file mode 100644
index 0000000..452176e
--- /dev/null
+++ b/exec/lib/BackendRuntimeConfig.php
@@ -0,0 +1,51 @@
+<?php
+declare(strict_types=1);
+
+final class BackendRuntimeConfig
+{
+    public static function sync(Settings $settings, string $backendScript, string $statePath = Settings::CONFIG_DIR . '/backend-state.json', string $errorLog = ''): void
+    {
+        $desired = $settings->backendMode();
+        $current = self::currentBackend($statePath);
+        if ($current === $desired) {
+            return;
+        }
+
+        if (!is_file($backendScript) || !is_executable($backendScript)) {
+            self::log($errorLog, 'Backend script not executable: ' . $backendScript);
+            return;
+        }
+
+        $process = proc_open([$backendScript, $desired], [['pipe', 'r'], ['pipe', 'w'], ['pipe', 'w']], $pipes);
+        if (!is_resource($process)) {
+            self::log($errorLog, 'Could not start backend script.');
+            return;
+        }
+        fclose($pipes[0]);
+        stream_get_contents($pipes[1]);
+        $stderr = stream_get_contents($pipes[2]);
+        fclose($pipes[1]);
+        fclose($pipes[2]);
+        $code = proc_close($process);
+        if ($code !== 0) {
+            self::log($errorLog, 'Backend script failed with code ' . $code . ': ' . trim($stderr));
+        }
+    }
+
+    private static function currentBackend(string $statePath): string
+    {
+        if (!is_file($statePath)) {
+            return '';
+        }
+        $data = json_decode((string)file_get_contents($statePath), true);
+        return is_array($data) ? (string)($data['active_backend'] ?? '') : '';
+    }
+
+    private static function log(string $errorLog, string $message): void
+    {
+        if ($errorLog === '') {
+            return;
+        }
+        @error_log('[' . date('c') . '] BACKEND_SYNC ' . $message . "\n", 3, $errorLog);
+    }
+}
diff --git a/exec/lib/RuleValidator.php b/exec/lib/RuleValidator.php
index 7bd4e60..d608669 100644
--- a/exec/lib/RuleValidator.php
+++ b/exec/lib/RuleValidator.php
@@ -53,7 +53,7 @@ final class RuleValidator
     {
         $value = trim($value);
         if ($mode === 'exact_hour') {
-            if (!preg_match('/^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:00$/', $value)) {
+            if (!preg_match('/^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}$/', $value)) {
                 throw new InvalidArgumentException('Nieprawidłowa data lub godzina.');
             }
             $dt = DateTimeImmutable::createFromFormat('!Y-m-d\TH:i', $value, $tz);
diff --git a/exec/lib/Settings.php b/exec/lib/Settings.php
index 119958f..fbdf9af 100644
--- a/exec/lib/Settings.php
+++ b/exec/lib/Settings.php
@@ -51,7 +51,7 @@ final class Settings
             'DEFAULT_PLUGIN_LANGUAGE' => 'en',
             'DEFAULT_ENABLE' => 'true',
             'GLOBAL_AUTORESPONDER_TIMEZONE' => 'Europe/Warsaw',
-            'GLOBAL_AUTORESPONDER_SCHEDULE_MODE' => 'exact_hour',
+            'GLOBAL_AUTORESPONDER_BACKEND' => 'da',
             'GLOBAL_AUTORESPONDER_REPLY_EVERY_MESSAGE' => 'false',
             'GLOBAL_AUTORESPONDER_REPEAT_MINUTES' => '1440',
             'GLOBAL_AUTORESPONDER_DYNAMIC_MAILBOX_SCOPE' => 'true',
@@ -93,9 +93,14 @@ final class Settings
         return $this->getString('GLOBAL_AUTORESPONDER_TIMEZONE', 'Europe/Warsaw');
     }
 
+    public function backendMode(): string
+    {
+        return $this->getString('GLOBAL_AUTORESPONDER_BACKEND', 'da');
+    }
+
     public function scheduleMode(): string
     {
-        return $this->getString('GLOBAL_AUTORESPONDER_SCHEDULE_MODE', 'exact_hour');
+        return $this->backendMode() === 'da' ? 'directadmin_period' : 'exact_hour';
     }
 
     public function replyEveryMessage(): bool
@@ -148,8 +153,8 @@ final class Settings
         } catch (Throwable) {
             throw new InvalidArgumentException('Invalid timezone: ' . $this->timezone());
         }
-        if (!in_array($this->scheduleMode(), ['exact_hour', 'directadmin_period'], true)) {
-            throw new InvalidArgumentException('Invalid schedule mode: ' . $this->scheduleMode());
+        if (!in_array($this->backendMode(), ['da', 'exim'], true)) {
+            throw new InvalidArgumentException('Invalid backend mode: ' . $this->backendMode());
         }
         if ($this->repeatMinutes() < 0) {
             throw new InvalidArgumentException('Invalid repeat minutes');
diff --git a/lang/en.php b/lang/en.php
index e12cfe9..8ea9bc7 100644
--- a/lang/en.php
+++ b/lang/en.php
@@ -12,6 +12,7 @@ return [
     'Preview autoresponder' => 'Preview autoresponder',
     'Subject' => 'Subject',
     'Message body' => 'Message body',
+    'Response content' => 'Response content',
     'Status' => 'Status',
     'Enabled' => 'Enabled',
     'Disabled' => 'Disabled',
@@ -19,6 +20,11 @@ return [
     'End date' => 'End date',
     'Start hour' => 'Start hour',
     'End hour' => 'End hour',
+    'Time' => 'Time',
+    'Time of day' => 'Time of day',
+    'Morning' => 'Morning',
+    'Afternoon' => 'Afternoon',
+    'Evening' => 'Evening',
     'Save autoresponder' => 'Save autoresponder',
     'Save changes' => 'Save changes',
     'Cancel' => 'Cancel',
@@ -36,4 +42,15 @@ return [
     'Rule deleted.' => 'Rule deleted.',
     'Rule status changed.' => 'Rule status changed.',
     'All valid POP/IMAP mailboxes in this account' => 'All valid POP/IMAP mailboxes in this account',
+    'Rule not found' => 'Rule not found',
+    'Sending period' => 'Sending period',
+    'Scope' => 'Scope',
+    'Actions' => 'Actions',
+    'Dynamic' => 'Dynamic',
+    'Snapshot' => 'Snapshot',
+    'To' => 'to',
+    'Back' => 'Back',
+    'Rule details' => 'Rule details',
+    'Selected' => 'Selected',
+    'Deleting this rule will disable the automatic reply created by this rule for covered mailboxes.' => 'Deleting this rule will disable the automatic reply created by this rule for covered mailboxes.',
 ];
diff --git a/lang/pl.php b/lang/pl.php
index 1ded965..097ec4a 100644
--- a/lang/pl.php
+++ b/lang/pl.php
@@ -12,6 +12,7 @@ return [
     'Preview autoresponder' => 'Podgląd autorespondera',
     'Subject' => 'Temat',
     'Message body' => 'Treść wiadomości',
+    'Response content' => 'Treść odpowiedzi',
     'Status' => 'Status',
     'Enabled' => 'Włączony',
     'Disabled' => 'Wyłączony',
@@ -19,6 +20,11 @@ return [
     'End date' => 'Data zakończenia',
     'Start hour' => 'Godzina rozpoczęcia',
     'End hour' => 'Godzina zakończenia',
+    'Time' => 'Czas',
+    'Time of day' => 'Pora dnia',
+    'Morning' => 'Rano',
+    'Afternoon' => 'Po południu',
+    'Evening' => 'Wieczorem',
     'Save autoresponder' => 'Zapisz autoresponder',
     'Save changes' => 'Zapisz zmiany',
     'Cancel' => 'Anuluj',
@@ -36,4 +42,15 @@ return [
     'Rule deleted.' => 'Reguła została usunięta.',
     'Rule status changed.' => 'Status reguły został zmieniony.',
     'All valid POP/IMAP mailboxes in this account' => 'Wszystkie prawidłowe skrzynki POP/IMAP konta',
+    'Rule not found' => 'Nie znaleziono reguły',
+    'Sending period' => 'Okres wysyłki',
+    'Scope' => 'Zakres',
+    'Actions' => 'Akcje',
+    'Dynamic' => 'Dynamiczny',
+    'Snapshot' => 'Migawka',
+    'To' => 'do',
+    'Back' => 'Powrót',
+    'Rule details' => 'Szczegóły reguły',
+    'Selected' => 'Wybrano',
+    'Deleting this rule will disable the automatic reply created by this rule for covered mailboxes.' => 'Usunięcie reguły wyłączy odpowiedź automatyczną utworzoną przez tę regułę dla objętych skrzynek.',
 ];
diff --git a/plugin-settings.conf b/plugin-settings.conf
index 5f4c000..8ddabf1 100644
--- a/plugin-settings.conf
+++ b/plugin-settings.conf
@@ -8,10 +8,10 @@ DEFAULT_ENABLE=true
 # Strefa czasu używana do interpretacji i wyświetlania dat rozpoczęcia oraz zakończenia.
 GLOBAL_AUTORESPONDER_TIMEZONE=Europe/Warsaw
 
-# Tryb harmonogramu.
-# exact_hour = wybór dnia i godziny.
-# directadmin_period = wybór dnia oraz morning/afternoon/evening zgodnie z API DirectAdmin.
-GLOBAL_AUTORESPONDER_SCHEDULE_MODE=exact_hour
+# Tryb pracy pluginu.
+# da = użycie natywnych autoresponderów DirectAdmin.
+# exim = własna obsługa z możliwością podania dokładnej godziny i minuty.
+GLOBAL_AUTORESPONDER_BACKEND=da
 
 # Czy odpowiadać automatycznie na każdą kwalifikującą się wiadomość.
 GLOBAL_AUTORESPONDER_REPLY_EVERY_MESSAGE=false
diff --git a/plugin.conf b/plugin.conf
index 664b450..7ee32fd 100644
--- a/plugin.conf
+++ b/plugin.conf
@@ -2,6 +2,6 @@ name=global-autoresponder
 id=global-autoresponder
 type=user
 author=HITME.PL
-version=1.0.2
+version=1.0.3
 active=no
 installed=no
diff --git a/tests/backend_runtime_config_test.php b/tests/backend_runtime_config_test.php
new file mode 100644
index 0000000..a943c89
--- /dev/null
+++ b/tests/backend_runtime_config_test.php
@@ -0,0 +1,21 @@
+<?php
+declare(strict_types=1);
+
+require_once PLUGIN_ROOT . '/exec/lib/Settings.php';
+require_once PLUGIN_ROOT . '/exec/lib/BackendRuntimeConfig.php';
+
+test('backend runtime sync invokes backend script when setting changes', function (): void {
+    $settingsPath = TEST_TMP . '/backend-runtime.conf';
+    test_write($settingsPath, "GLOBAL_AUTORESPONDER_BACKEND=exim\n");
+    $settings = Settings::load($settingsPath);
+
+    $script = TEST_TMP . '/backend.sh';
+    test_write($script, "#!/bin/sh\necho \"$1\" >> " . escapeshellarg(TEST_TMP . '/called.log') . "\nmkdir -p " . escapeshellarg(TEST_TMP . '/config') . "\nprintf '{\"active_backend\":\"%s\"}\\n' \"$1\" > " . escapeshellarg(TEST_TMP . '/config/backend-state.json') . "\n");
+    chmod($script, 0700);
+
+    BackendRuntimeConfig::sync($settings, $script, TEST_TMP . '/config/backend-state.json');
+    assert_same("exim\n", file_get_contents(TEST_TMP . '/called.log'));
+
+    BackendRuntimeConfig::sync($settings, $script, TEST_TMP . '/config/backend-state.json');
+    assert_same("exim\n", file_get_contents(TEST_TMP . '/called.log'), 'Script should not run again when backend is already active');
+});
diff --git a/tests/bootstrap_test.php b/tests/bootstrap_test.php
index 95ed842..b302d32 100644
--- a/tests/bootstrap_test.php
+++ b/tests/bootstrap_test.php
@@ -10,7 +10,7 @@ test('settings validate defaults and external paths', function (): void {
         'DEFAULT_PLUGIN_LANGUAGE=pl',
         'DEFAULT_ENABLE=false',
         'GLOBAL_AUTORESPONDER_TIMEZONE=Europe/Warsaw',
-        'GLOBAL_AUTORESPONDER_SCHEDULE_MODE=exact_hour',
+        'GLOBAL_AUTORESPONDER_BACKEND=exim',
         'GLOBAL_AUTORESPONDER_REPLY_EVERY_MESSAGE=false',
         'GLOBAL_AUTORESPONDER_REPEAT_MINUTES=60',
         'GLOBAL_AUTORESPONDER_DYNAMIC_MAILBOX_SCOPE=true',
@@ -23,6 +23,7 @@ test('settings validate defaults and external paths', function (): void {
     assert_false($settings->defaultEnable());
     assert_same('Europe/Warsaw', $settings->timezone());
     assert_same('exact_hour', $settings->scheduleMode());
+    assert_same('exim', $settings->backendMode());
     assert_same(60, $settings->repeatMinutes());
     assert_same('/usr/local/hitme_plugins/global-autoresponders/config', Settings::CONFIG_DIR);
     assert_same('/usr/local/hitme_plugins/global-autoresponders/data', Settings::DATA_DIR);
@@ -30,7 +31,7 @@ test('settings validate defaults and external paths', function (): void {
 
 test('settings reject invalid timezone and schedule mode', function (): void {
     $path = TEST_TMP . '/bad-settings.conf';
-    test_write($path, "GLOBAL_AUTORESPONDER_TIMEZONE=Not/AZone\nGLOBAL_AUTORESPONDER_SCHEDULE_MODE=bad\n");
+    test_write($path, "GLOBAL_AUTORESPONDER_TIMEZONE=Not/AZone\nGLOBAL_AUTORESPONDER_BACKEND=bad\n");
     try {
         Settings::load($path);
     } catch (InvalidArgumentException $e) {
@@ -40,6 +41,19 @@ test('settings reject invalid timezone and schedule mode', function (): void {
     throw new RuntimeException('Expected invalid settings to fail');
 });
 
+test('backend mode derives schedule mode', function (): void {
+    $path = TEST_TMP . '/backend.conf';
+    test_write($path, "GLOBAL_AUTORESPONDER_BACKEND=da\n");
+    $settings = Settings::load($path);
+    assert_same('da', $settings->backendMode());
+    assert_same('directadmin_period', $settings->scheduleMode());
+
+    test_write($path, "GLOBAL_AUTORESPONDER_BACKEND=exim\n");
+    $settings = Settings::load($path);
+    assert_same('exim', $settings->backendMode());
+    assert_same('exact_hour', $settings->scheduleMode());
+});
+
 test('directadmin user access follows DEFAULT_ENABLE and per-user overrides', function (): void {
     $settingsPath = TEST_TMP . '/access.conf';
     test_write($settingsPath, "DEFAULT_ENABLE=false\n");
diff --git a/tests/handler_test.php b/tests/handler_test.php
index 0dabe27..11ae277 100644
--- a/tests/handler_test.php
+++ b/tests/handler_test.php
@@ -28,3 +28,51 @@ test('directadmin user hooks are clickable and point to reserved icon path', fun
     assert_contains('<a href="/CMD_PLUGINS/global-autoresponder/index.html"', $txt);
     assert_contains('Globalne autorespondery', $txt);
 });
+
+test('rule form uses minute time input and no summary box in exim mode', function (): void {
+    require_once PLUGIN_ROOT . '/exec/lib/Settings.php';
+    require_once PLUGIN_ROOT . '/exec/lib/Lang.php';
+    require_once PLUGIN_ROOT . '/exec/lib/DirectAdminUser.php';
+    require_once PLUGIN_ROOT . '/exec/lib/CsrfGuard.php';
+    require_once PLUGIN_ROOT . '/exec/lib/RuleRepository.php';
+    require_once PLUGIN_ROOT . '/exec/lib/AuditLog.php';
+    require_once PLUGIN_ROOT . '/exec/lib/AppContext.php';
+    require_once PLUGIN_ROOT . '/exec/handlers/_form_helpers.php';
+
+    $settingsPath = TEST_TMP . '/form.conf';
+    test_write($settingsPath, "DEFAULT_PLUGIN_LANGUAGE=pl\nGLOBAL_AUTORESPONDER_BACKEND=exim\n");
+    $settings = Settings::load($settingsPath);
+    $ctx = new AppContext(
+        new DirectAdminUser('alice', 'enhanced', 'pl', TEST_TMP . '/config'),
+        $settings,
+        new RuleRepository(TEST_TMP . '/data'),
+        new CsrfGuard('secret', 'alice', 'sid'),
+        Lang::load('pl', $settings),
+        new AuditLog(TEST_TMP . '/audit.log')
+    );
+
+    $html = render_rule_form($ctx, 'create', null);
+    assert_contains('type="time"', $html);
+    assert_contains('step="60"', $html);
+    assert_false(strpos($html, 'summary-card') !== false, 'Summary box should not be rendered in create/edit form');
+    assert_contains('Temat', $html);
+    assert_contains('Treść wiadomości', $html);
+});
+
+test('rule form uses native period selector in da mode', function (): void {
+    $settingsPath = TEST_TMP . '/form-da.conf';
+    test_write($settingsPath, "DEFAULT_PLUGIN_LANGUAGE=pl\nGLOBAL_AUTORESPONDER_BACKEND=da\n");
+    $settings = Settings::load($settingsPath);
+    $ctx = new AppContext(
+        new DirectAdminUser('alice', 'enhanced', 'pl', TEST_TMP . '/config'),
+        $settings,
+        new RuleRepository(TEST_TMP . '/data'),
+        new CsrfGuard('secret', 'alice', 'sid'),
+        Lang::load('pl', $settings),
+        new AuditLog(TEST_TMP . '/audit.log')
+    );
+    $html = render_rule_form($ctx, 'create', null);
+    assert_contains('name="start_value_period"', $html);
+    assert_contains('Rano', $html);
+    assert_false(strpos($html, 'type="time"') !== false);
+});
diff --git a/tests/rule_validator_test.php b/tests/rule_validator_test.php
index 3f9621d..1e93e2b 100644
--- a/tests/rule_validator_test.php
+++ b/tests/rule_validator_test.php
@@ -6,22 +6,37 @@ require_once PLUGIN_ROOT . '/exec/lib/RuleValidator.php';
 
 test('rule validator normalizes exact hour schedule', function (): void {
     $settingsPath = TEST_TMP . '/validator.conf';
-    test_write($settingsPath, "GLOBAL_AUTORESPONDER_TIMEZONE=Europe/Warsaw\nGLOBAL_AUTORESPONDER_SCHEDULE_MODE=exact_hour\n");
+    test_write($settingsPath, "GLOBAL_AUTORESPONDER_TIMEZONE=Europe/Warsaw\nGLOBAL_AUTORESPONDER_BACKEND=exim\n");
     $settings = Settings::load($settingsPath);
     $rule = RuleValidator::validate([
         'subject' => 'Urlop',
         'body' => "Dzień dobry\r\nWracam jutro",
-        'start_value' => '2026-06-10T09:00',
-        'end_value' => '2026-06-24T17:00',
+        'start_value' => '2026-06-10T09:37',
+        'end_value' => '2026-06-24T17:12',
         'enabled' => '1',
     ], $settings);
 
     assert_same('Urlop', $rule['subject']);
     assert_same("Dzień dobry\nWracam jutro", $rule['body']);
     assert_same('exact_hour', $rule['schedule_mode']);
+    assert_same('2026-06-10T09:37', $rule['start_value']);
     assert_true($rule['start_ts'] < $rule['end_ts']);
 });
 
+test('rule validator accepts da period schedule when backend is da', function (): void {
+    $settingsPath = TEST_TMP . '/validator-da.conf';
+    test_write($settingsPath, "GLOBAL_AUTORESPONDER_BACKEND=da\n");
+    $settings = Settings::load($settingsPath);
+    $rule = RuleValidator::validate([
+        'subject' => 'Urlop',
+        'body' => 'Body',
+        'start_value' => '2026-06-10|morning',
+        'end_value' => '2026-06-24|evening',
+        'enabled' => '1',
+    ], $settings);
+    assert_same('directadmin_period', $rule['schedule_mode']);
+});
+
 test('rule validator rejects header injection and reversed dates', function (): void {
     $settings = Settings::load(TEST_TMP . '/missing.conf');
     try {