diff --git a/mailpoet/lib/Cron/Workers/Scheduler.php b/mailpoet/lib/Cron/Workers/Scheduler.php
index 58f9b77ecd..0fb8130b13 100644
--- a/mailpoet/lib/Cron/Workers/Scheduler.php
+++ b/mailpoet/lib/Cron/Workers/Scheduler.php
@@ -152,7 +152,7 @@ class Scheduler {
         } elseif ($newsletter->getType() === NewsletterEntity::TYPE_WELCOME) {
           $this->processWelcomeNewsletter($newsletter, $task);
         } elseif ($newsletter->getType() === NewsletterEntity::TYPE_NOTIFICATION) {
-          $this->processPostNotificationNewsletter($newsletter, $legacyQueue);
+          $this->processPostNotificationNewsletter($newsletter, $task);
         } elseif ($newsletter->getType() === NewsletterEntity::TYPE_STANDARD) {
           $this->processScheduledStandardNewsletter($newsletter, $legacyQueue);
         } elseif ($newsletter->getType() === NewsletterEntity::TYPE_AUTOMATIC) {
@@ -198,10 +198,10 @@ class Scheduler {
     return true;
   }
 
-  public function processPostNotificationNewsletter(NewsletterEntity $newsletter, SendingTask $queue) {
+  public function processPostNotificationNewsletter(NewsletterEntity $newsletter, ScheduledTaskEntity $task) {
     $this->loggerFactory->getLogger(LoggerFactory::TOPIC_POST_NOTIFICATIONS)->info(
       'process post notification in scheduler',
-      ['newsletter_id' => $newsletter->getId(), 'task_id' => $queue->taskId]
+      ['newsletter_id' => $newsletter->getId(), 'task_id' => $task->getId()]
     );
 
     // ensure that segments exist
@@ -209,24 +209,21 @@ class Scheduler {
     if (empty($segments)) {
       $this->loggerFactory->getLogger(LoggerFactory::TOPIC_POST_NOTIFICATIONS)->info(
         'post notification no segments',
-        ['newsletter_id' => $newsletter->getId(), 'task_id' => $queue->taskId]
+        ['newsletter_id' => $newsletter->getId(), 'task_id' => $task->getId()]
       );
-      return $this->deleteQueueOrUpdateNextRunDate($queue, $newsletter);
+      $this->deleteQueueOrUpdateNextRunDate($task, $newsletter);
+      return false;
     }
 
     // ensure that subscribers are in segments
-    $taskModel = $queue->task();
-    $taskEntity = $this->scheduledTasksRepository->findOneById($taskModel->id);
-    if ($taskEntity instanceof ScheduledTaskEntity) {
-      $subscribersCount = $this->subscribersFinder->addSubscribersToTaskFromSegments($taskEntity, $segments, $newsletter->getFilterSegmentId());
-    }
-
+    $subscribersCount = $this->subscribersFinder->addSubscribersToTaskFromSegments($task, $segments, $newsletter->getFilterSegmentId());
     if (empty($subscribersCount)) {
       $this->loggerFactory->getLogger(LoggerFactory::TOPIC_POST_NOTIFICATIONS)->info(
         'post notification no subscribers',
-        ['newsletter_id' => $newsletter->getId(), 'task_id' => $queue->taskId, 'segment_ids' => $segments]
+        ['newsletter_id' => $newsletter->getId(), 'task_id' => $task->getId(), 'segment_ids' => $segments]
       );
-      return $this->deleteQueueOrUpdateNextRunDate($queue, $newsletter);
+      $this->deleteQueueOrUpdateNextRunDate($task, $newsletter);
+      return false;
     }
 
     // create a duplicate newsletter that acts as a history record
@@ -235,25 +232,28 @@ class Scheduler {
     } catch (\Exception $exception) {
       $this->loggerFactory->getLogger(LoggerFactory::TOPIC_POST_NOTIFICATIONS)->error(
         'creating post notification history failed',
-        ['newsletter_id' => $newsletter->getId(), 'task_id' => $queue->taskId, 'error' => $exception->getMessage()]
+        ['newsletter_id' => $newsletter->getId(), 'task_id' => $task->getId(), 'error' => $exception->getMessage()]
       );
       return false;
     }
 
     // queue newsletter for delivery
-    $queue->newsletterId = (int)$notificationHistory->getId();
-    $queue->updateCount();
-    $queue->status = null;
-    $queue->save();
-    $this->updateScheduledTaskEntity($queue);
-
-    // Because there is mixed usage of the old and new model, we want to be sure about the correct state
-    $this->newslettersRepository->refresh($notificationHistory);
-    $queue->getSendingQueueEntity(); // This call refreshes sending queue entity
+    $queue = $task->getSendingQueue();
+    if (!$queue) {
+      $this->loggerFactory->getLogger(LoggerFactory::TOPIC_POST_NOTIFICATIONS)->error(
+        'post notification no queue',
+        ['newsletter_id' => $newsletter->getId(), 'task_id' => $task->getId()]
+      );
+      return false;
+    }
+    $queue->setNewsletter($notificationHistory);
+    $this->sendingQueuesRepository->updateCounts($queue);
+    $task->setStatus(null);
+    $this->scheduledTasksRepository->flush();
 
     $this->loggerFactory->getLogger(LoggerFactory::TOPIC_POST_NOTIFICATIONS)->info(
       'post notification set status to sending',
-      ['newsletter_id' => $newsletter->getId(), 'task_id' => $queue->taskId]
+      ['newsletter_id' => $newsletter->getId(), 'task_id' => $task->getId()]
     );
     return true;
   }
@@ -418,21 +418,17 @@ class Scheduler {
     return true;
   }
 
-  public function deleteQueueOrUpdateNextRunDate($queue, NewsletterEntity $newsletter) {
+  public function deleteQueueOrUpdateNextRunDate(ScheduledTaskEntity $task, NewsletterEntity $newsletter) {
     if ($newsletter->getOptionValue('intervalType') === PostNotificationScheduler::INTERVAL_IMMEDIATELY) {
-      $queue->delete();
-      $this->updateScheduledTaskEntity($queue, true);
-      return;
+      $this->deleteByTask($task);
     } else {
-      $nextRunDate = $this->scheduler->getNextRunDate($newsletter->getOptionValue('schedule'));
+      $nextRunDate = $this->scheduler->getNextRunDateTime($newsletter->getOptionValue('schedule'));
       if (!$nextRunDate) {
-        $queue->delete();
-        $this->updateScheduledTaskEntity($queue, true);
+        $this->deleteByTask($task);
         return;
       }
-      $queue->scheduledAt = $nextRunDate;
-      $queue->save();
-      $this->updateScheduledTaskEntity($queue);
+      $task->setScheduledAt($nextRunDate);
+      $this->scheduledTasksRepository->flush();
     }
   }
 
diff --git a/mailpoet/lib/Newsletter/Sending/SendingQueuesRepository.php b/mailpoet/lib/Newsletter/Sending/SendingQueuesRepository.php
index b94092fba7..2ec5933109 100644
--- a/mailpoet/lib/Newsletter/Sending/SendingQueuesRepository.php
+++ b/mailpoet/lib/Newsletter/Sending/SendingQueuesRepository.php
@@ -205,4 +205,20 @@ class SendingQueuesRepository extends Repository {
     $queue->setMeta($meta);
     $this->flush();
   }
+
+  public function updateCounts(SendingQueueEntity $queue, ?int $count = null): void {
+    if ($count) {
+      // increment/decrement counts based on known subscriber count, don't exceed the bounds
+      $queue->setCountProcessed(min($queue->getCountProcessed() + $count, $queue->getCountTotal()));
+      $queue->setCountToProcess(max($queue->getCountToProcess() - $count, 0));
+    } else {
+      // query DB to update counts, slower but more accurate, to be used if count isn't known
+      $task = $queue->getTask();
+      $processed = $task ? $this->scheduledTaskSubscribersRepository->countProcessed($task) : 0;
+      $unprocessed = $task ? $this->scheduledTaskSubscribersRepository->countUnprocessed($task) : 0;
+      $queue->setCountProcessed($processed);
+      $queue->setCountToProcess($unprocessed);
+      $queue->setCountTotal($processed + $unprocessed);
+    }
+  }
 }