diff --git a/app/Livewire/Admin/Maintenance.php b/app/Livewire/Admin/Maintenance.php
index 8a9f27a..3ebd579 100644
--- a/app/Livewire/Admin/Maintenance.php
+++ b/app/Livewire/Admin/Maintenance.php
@@ -124,6 +124,22 @@ class Maintenance extends Component
         $this->dispatch('notify', message: __('maintenance.published'));
     }
 
+    /**
+     * Re-run announcements for a published window. Idempotent (ledger-guarded),
+     * so it only fills gaps — the retry path when a transient queue outage left
+     * some affected customers un-notified.
+     */
+    public function resend(string $uuid): void
+    {
+        $this->authorize('maintenance.manage');
+        $window = MaintenanceWindow::query()->where('uuid', $uuid)->first();
+        if ($window === null || $window->state !== 'scheduled') {
+            return;
+        }
+        $this->sendAnnouncements($window);
+        $this->dispatch('notify', message: __('maintenance.notified'));
+    }
+
     public function cancel(string $uuid): void
     {
         $this->authorize('maintenance.manage');
@@ -176,6 +192,7 @@ class Maintenance extends Component
                 'hosts' => $w->hosts_count,
                 'affected' => $w->affectedCustomers()->count(),
                 'is_draft' => $w->state === 'draft',
+                'notifiable' => $w->state === 'scheduled' && in_array($w->derivedState(), ['upcoming', 'active'], true),
                 'cancellable' => in_array($w->derivedState(), ['draft', 'upcoming', 'active'], true),
             ]);
 
diff --git a/app/Livewire/Admin/Settings.php b/app/Livewire/Admin/Settings.php
index 7f9835e..d1ee108 100644
--- a/app/Livewire/Admin/Settings.php
+++ b/app/Livewire/Admin/Settings.php
@@ -7,6 +7,7 @@ use App\Models\User;
 use Illuminate\Support\Facades\DB;
 use Illuminate\Support\Facades\Hash;
 use Illuminate\Support\Str;
+use Spatie\Permission\Models\Role;
 use Livewire\Attributes\Layout;
 use Livewire\Attributes\Validate;
 use Livewire\Component;
@@ -105,6 +106,10 @@ class Settings extends Component
         }
 
         $result = DB::transaction(function () use ($id, $role) {
+            // Serialize on the Owner role so the global owner count can't be
+            // raced to zero by concurrent demotions of different owners.
+            Role::query()->where('name', 'Owner')->lockForUpdate()->first();
+
             $target = User::query()->whereKey($id)->lockForUpdate()->first();
             if ($target === null) {
                 return 'gone';
@@ -138,6 +143,8 @@ class Settings extends Component
         $this->authorize('staff.manage');
 
         $result = DB::transaction(function () use ($id) {
+            Role::query()->where('name', 'Owner')->lockForUpdate()->first();
+
             $target = User::query()->whereKey($id)->lockForUpdate()->first();
             if ($target === null || ! $target->isOperator()) {
                 return 'gone';
diff --git a/lang/de/maintenance.php b/lang/de/maintenance.php
index e5e2f93..757cbdd 100644
--- a/lang/de/maintenance.php
+++ b/lang/de/maintenance.php
@@ -31,6 +31,8 @@ return [
     'cancel' => 'Stornieren',
     'mail_note' => 'Beim Veröffentlichen erhalten betroffene Kunden eine Ankündigungs-E-Mail (aktuell Log/Mock).',
 
+    'notify_again' => 'Erneut benachrichtigen',
+    'notified' => 'Benachrichtigungen versendet.',
     'draft_saved' => 'Entwurf gespeichert.',
     'published' => 'Wartung veröffentlicht — Kunden werden benachrichtigt.',
     'cancelled' => 'Wartung storniert.',
diff --git a/lang/en/maintenance.php b/lang/en/maintenance.php
index 66b8e4b..dc38eee 100644
--- a/lang/en/maintenance.php
+++ b/lang/en/maintenance.php
@@ -31,6 +31,8 @@ return [
     'cancel' => 'Cancel',
     'mail_note' => 'On publish, affected customers receive an announcement email (currently log/mock).',
 
+    'notify_again' => 'Notify again',
+    'notified' => 'Notifications sent.',
     'draft_saved' => 'Draft saved.',
     'published' => 'Maintenance published — customers are being notified.',
     'cancelled' => 'Maintenance cancelled.',
diff --git a/resources/views/livewire/admin/maintenance.blade.php b/resources/views/livewire/admin/maintenance.blade.php
index 037a4db..12c5604 100644
--- a/resources/views/livewire/admin/maintenance.blade.php
+++ b/resources/views/livewire/admin/maintenance.blade.php
@@ -34,6 +34,9 @@
                                             @if ($w['is_draft'])
                                                 <button type="button" wire:click="publishExisting('{{ $w['uuid'] }}')" class="rounded-md border border-line px-2.5 py-1.5 text-xs font-semibold text-body hover:border-accent-border hover:text-accent-text">{{ __('maintenance.publish') }}</button>
                                             @endif
+                                            @if ($w['notifiable'])
+                                                <button type="button" wire:click="resend('{{ $w['uuid'] }}')" class="rounded-md border border-line px-2.5 py-1.5 text-xs font-semibold text-body hover:border-accent-border hover:text-accent-text">{{ __('maintenance.notify_again') }}</button>
+                                            @endif
                                             @if ($w['cancellable'])
                                                 <button type="button" wire:click="cancel('{{ $w['uuid'] }}')" class="rounded-md border border-line px-2.5 py-1.5 text-xs font-semibold text-muted hover:border-danger hover:text-danger">{{ __('maintenance.cancel') }}</button>
                                             @endif