diff --git a/lib/Cron/Workers/SendingQueue/SendingQueue.php b/lib/Cron/Workers/SendingQueue/SendingQueue.php
index ac1adf1595..9efa7caaeb 100644
--- a/lib/Cron/Workers/SendingQueue/SendingQueue.php
+++ b/lib/Cron/Workers/SendingQueue/SendingQueue.php
@@ -4,7 +4,6 @@ namespace MailPoet\Cron\Workers\SendingQueue;
 use MailPoet\Cron\CronHelper;
 use MailPoet\Cron\Workers\SendingQueue\Tasks\Mailer as MailerTask;
 use MailPoet\Cron\Workers\SendingQueue\Tasks\Newsletter as NewsletterTask;
-use MailPoet\Cron\Workers\SendingQueue\Tasks\Subscribers as SubscribersTask;
 use MailPoet\Mailer\MailerLog;
 use MailPoet\Models\SendingQueue as SendingQueueModel;
 use MailPoet\Models\StatisticsNewsletters as StatisticsNewslettersModel;
@@ -16,6 +15,7 @@ class SendingQueue {
   public $mailer_task;
   public $newsletter_task;
   public $timer;
+  const BATCH_SIZE = 50;
 
   function __construct($timer = false, $mailer_task = false, $newsletter_task = false) {
     $this->mailer_task = ($mailer_task) ? $mailer_task : new MailerTask();
@@ -39,8 +39,10 @@ class SendingQueue {
       $this->mailer_task->configureMailer($newsletter);
       // get subscribers
       $queue->subscribers = $queue->getSubscribers();
-      $subscriber_batches =
-        SubscribersTask::splitSubscribersIntoBatches($queue->subscribers['to_process']);
+      $subscriber_batches = array_chunk(
+        $queue->subscribers['to_process'],
+        self::BATCH_SIZE
+      );
       foreach($subscriber_batches as $subscribers_to_process_ids) {
         // abort if execution limit is reached
         CronHelper::enforceExecutionLimit($this->timer);
@@ -51,13 +53,12 @@ class SendingQueue {
         }, $found_subscribers);
         // if some subscribers weren't found, remove them from the processing list
         if(count($found_subscribers_ids) !== count($subscribers_to_process_ids)) {
-          $queue->subscribers = SubscribersTask::updateToProcessList(
-            $found_subscribers_ids,
+          $subscibers_to_remove = array_diff(
             $subscribers_to_process_ids,
-            $queue->subscribers
+            $found_subscribers_ids
           );
+          $queue->removeNonexistentSubscribers($subscibers_to_remove);
           if(!count($queue->subscribers['to_process'])) {
-            $this->updateQueue($queue);
             $this->newsletter_task->markNewsletterAsSent($newsletter);
             continue;
           }
@@ -140,22 +141,14 @@ class SendingQueue {
     );
     if(!$send_result) {
       // update failed/to process list
-      $queue->subscribers = SubscribersTask::updateFailedList(
-        $prepared_subscribers_ids,
-        $queue->subscribers
-      );
-      $queue = $this->updateQueue($queue);
+      $queue->updateFailedSubscribers($prepared_subscribers_ids);
     } else {
       // update processed/to process list
-      $queue->subscribers = SubscribersTask::updateProcessedList(
-        $prepared_subscribers_ids,
-        $queue->subscribers
-      );
+      $queue->updateProcessedSubscribers($prepared_subscribers_ids);
       // log statistics
       StatisticsNewslettersModel::createMultiple($statistics);
       // update the sent count
       $this->mailer_task->updateSentCount();
-      $queue = $this->updateQueue($queue);
       // enforce sending limit if there are still subscribers left to process
       if($queue->count_to_process) {
         MailerLog::enforceSendingLimit();
@@ -170,18 +163,4 @@ class SendingQueue {
       ->whereNull('status')
       ->findMany();
   }
-
-  function updateQueue($queue) {
-    $queue->count_processed =
-      count($queue->subscribers['processed']) + count($queue->subscribers['failed']);
-    $queue->count_to_process = count($queue->subscribers['to_process']);
-    $queue->count_failed = count($queue->subscribers['failed']);
-    $queue->count_total =
-      $queue->count_processed + $queue->count_to_process;
-    if(!$queue->count_to_process) {
-      $queue->processed_at = current_time('mysql');
-      $queue->status = SendingQueueModel::STATUS_COMPLETED;
-    }
-    return $queue->save();
-  }
 }
\ No newline at end of file
diff --git a/lib/Cron/Workers/SendingQueue/Tasks/Subscribers.php b/lib/Cron/Workers/SendingQueue/Tasks/Subscribers.php
deleted file mode 100644
index c33fb30dae..0000000000
--- a/lib/Cron/Workers/SendingQueue/Tasks/Subscribers.php
+++ /dev/null
@@ -1,63 +0,0 @@
-<?php
-namespace MailPoet\Cron\Workers\SendingQueue\Tasks;
-
-if(!defined('ABSPATH')) exit;
-
-class Subscribers {
-  const BATCH_SIZE = 50;
-
-  static function splitSubscribersIntoBatches(array $subscribers) {
-    return array_chunk(
-      $subscribers,
-      self::BATCH_SIZE
-    );
-  }
-
-  static function updateToProcessList(
-    $found_subscribers_ids,
-    $subscribers_to_process_ids,
-    $queue_subscribers
-  ) {
-    // compare existing subscribers to the ones that are queued for processing
-    $subscibers_to_exclude = array_diff(
-      $subscribers_to_process_ids,
-      $found_subscribers_ids
-    );
-    // remove nonexistent subscribers from the processing list
-    $queue_subscribers['to_process'] = array_values(
-      array_diff(
-        $queue_subscribers['to_process'],
-        $subscibers_to_exclude
-      )
-    );
-    return $queue_subscribers;
-  }
-
-  static function updateFailedList($failed_subscribers, $queue_subscribers) {
-    $queue_subscribers['failed'] = array_merge(
-      $queue_subscribers['failed'],
-      $failed_subscribers
-    );
-    $queue_subscribers['to_process'] = array_values(
-      array_diff(
-        $queue_subscribers['to_process'],
-        $failed_subscribers
-      )
-    );
-    return $queue_subscribers;
-  }
-
-  static function updateProcessedList($processed_subscribers, $queue_subscribers) {
-    $queue_subscribers['processed'] = array_merge(
-      $queue_subscribers['processed'],
-      $processed_subscribers
-    );
-    $queue_subscribers['to_process'] = array_values(
-      array_diff(
-        $queue_subscribers['to_process'],
-        $processed_subscribers
-      )
-    );
-    return $queue_subscribers;
-  }
-}
\ No newline at end of file
diff --git a/lib/Models/SendingQueue.php b/lib/Models/SendingQueue.php
index 47e25ea24f..891163922b 100644
--- a/lib/Models/SendingQueue.php
+++ b/lib/Models/SendingQueue.php
@@ -10,7 +10,7 @@ class SendingQueue extends Model {
   const STATUS_PAUSED = 'paused';
 
   function newsletter() {
-    return $this->has_one(__NAMESPACE__.'\Newsletter', 'id', 'newsletter_id');
+    return $this->has_one(__NAMESPACE__ . '\Newsletter', 'id', 'newsletter_id');
   }
 
   function pause() {
@@ -84,4 +84,62 @@ class SendingQueue extends Model {
       : $this->subscribers;
     return $model;
   }
+
+  function removeNonexistentSubscribers($subscribers_to_remove) {
+    $subscribers = $this->getSubscribers();
+    $subscribers['to_process'] = array_values(
+      array_diff(
+        $subscribers['to_process'],
+        $subscribers_to_remove
+      )
+    );
+    $this->subscribers = $subscribers;
+    $this->updateCount();
+  }
+
+  function updateFailedSubscribers($failed_subscribers) {
+    $subscribers = $this->getSubscribers();
+    $subscribers['failed'] = array_merge(
+      $subscribers['failed'],
+      $failed_subscribers
+    );
+    $subscribers['to_process'] = array_values(
+      array_diff(
+        $subscribers['to_process'],
+        $failed_subscribers
+      )
+    );
+    $this->subscribers = $subscribers;
+    $this->updateCount();
+  }
+
+  function updateProcessedSubscribers($processed_subscribers) {
+    $subscribers = $this->getSubscribers();
+    $subscribers['processed'] = array_merge(
+      $subscribers['processed'],
+      $processed_subscribers
+    );
+    $subscribers['to_process'] = array_values(
+      array_diff(
+        $subscribers['to_process'],
+        $processed_subscribers
+      )
+    );
+    $this->subscribers = $subscribers;
+    $this->updateCount();
+  }
+
+  function updateCount() {
+    $this->subscribers = $this->getSubscribers();
+    $this->count_processed =
+      count($this->subscribers['processed']) + count($this->subscribers['failed']);
+    $this->count_to_process = count($this->subscribers['to_process']);
+    $this->count_failed = count($this->subscribers['failed']);
+    $this->count_total = $this->count_processed + $this->count_to_process;
+    if(!$this->count_to_process) {
+      $this->processed_at = current_time('mysql');
+      $this->status = self::STATUS_COMPLETED;
+    }
+    return $this->save();
+  }
 }
\ No newline at end of file
diff --git a/tests/unit/Cron/Workers/SendingQueue/Tasks/SubscribersTest.php b/tests/unit/Cron/Workers/SendingQueue/Tasks/SubscribersTest.php
deleted file mode 100644
index c0f7b271f0..0000000000
--- a/tests/unit/Cron/Workers/SendingQueue/Tasks/SubscribersTest.php
+++ /dev/null
@@ -1,96 +0,0 @@
-<?php
-use MailPoet\Cron\Workers\SendingQueue\Tasks\Subscribers;
-
-if(!defined('ABSPATH')) exit;
-
-class SubscribersTaskTest extends MailPoetTest {
-  function testItCanSplitSubscribersInBatches() {
-    $subscribers = range(1, 200);
-    $split_subscribers = Subscribers::splitSubscribersIntoBatches($subscribers);
-    expect(count($split_subscribers))->equals(200 / Subscribers::BATCH_SIZE);
-    expect(count($split_subscribers[0]))->equals(Subscribers::BATCH_SIZE);
-  }
-
-  function testItCanRemoveNonexistentSubscribersFromListOfSubscribersToProcess() {
-    $queue_subscribers = array(
-      'to_process' => range(1, 5)
-    );
-    $subscribers_found = array(
-      1,
-      2,
-      5
-    );
-    $subscribers_to_process = array(
-      3,
-      4
-    );
-    $updated_queue_subscribers = Subscribers::updateToProcessList(
-      $subscribers_found,
-      $subscribers_to_process,
-      $queue_subscribers
-    );
-    expect($updated_queue_subscribers)->equals(
-      array(
-        'to_process' => array(
-          1,
-          2,
-          5
-        )
-      )
-    );
-  }
-
-  function testItCanUpdateListOfFailedSubscribers() {
-    $queue_subscribers = array(
-      'to_process' => range(1, 5),
-      'failed' => array()
-    );
-    $failed_subscribers = array(
-      1
-    );
-    $updated_queue_subscribers = Subscribers::updateFailedList(
-      $failed_subscribers,
-      $queue_subscribers
-    );
-    expect($updated_queue_subscribers)->equals(
-      array(
-        'to_process' => array(
-          2,
-          3,
-          4,
-          5
-        ),
-        'failed' => array(
-          1
-        )
-      )
-    );
-  }
-
-  function testItCanUpdateListOfProcessedSubscribers() {
-    $queue_subscribers = array(
-      'to_process' => range(1, 5),
-      'processed' => array()
-    );
-    $processed_subscribers = array(
-      1
-    );
-    $updated_queue_subscribers = Subscribers::updateProcessedList(
-      $processed_subscribers,
-      $queue_subscribers
-    );
-    expect($updated_queue_subscribers)->equals(
-      array(
-        'to_process' => array(
-          2,
-          3,
-          4,
-          5
-        ),
-        'processed' => array(
-          1
-        )
-      )
-    );
-  }
-}
\ No newline at end of file