diff --git a/lib/Cron/Workers/SendingQueue/Tasks/Posts.php b/lib/Cron/Workers/SendingQueue/Tasks/Posts.php
index 3c31edaa94..2b670b60ff 100644
--- a/lib/Cron/Workers/SendingQueue/Tasks/Posts.php
+++ b/lib/Cron/Workers/SendingQueue/Tasks/Posts.php
@@ -45,7 +45,7 @@ class Posts {
   }
 
   public function getAlcPostsCount($renderedNewsletter, \MailPoet\Models\Newsletter $newsletter) {
-    $templatePostsCount = substr_count($newsletter->body, 'data-post-id');
+    $templatePostsCount = substr_count($newsletter->getBodyString(), 'data-post-id');
     $newsletterPostsCount = substr_count($renderedNewsletter['html'], 'data-post-id');
     return $newsletterPostsCount - $templatePostsCount;
   }
diff --git a/lib/Models/Newsletter.php b/lib/Models/Newsletter.php
index 714e4d9f5f..d0aa34f7e9 100644
--- a/lib/Models/Newsletter.php
+++ b/lib/Models/Newsletter.php
@@ -34,7 +34,7 @@ use function MailPoetVendor\array_column;
  * @property array $segments
  * @property string $subject
  * @property string $preheader
- * @property string $body
+ * @property string|array|null $body
  * @property string|null $schedule
  * @property bool|null $isScheduled
  * @property string|null $scheduledAt
@@ -116,9 +116,7 @@ class Newsletter extends Model {
     }
 
     if (isset($this->body) && ($this->body !== false)) {
-      if (is_array($this->body)) {
-        $this->body = (string)json_encode($this->body);
-      }
+      $this->body = $this->getBodyString();
       $this->set(
         'body',
         $this->body
@@ -155,7 +153,7 @@ class Newsletter extends Model {
 
   public function setStatus($status = null) {
     if ($status === self::STATUS_ACTIVE) {
-      if (!$this->body || empty(json_decode($this->body))) {
+      if (!$this->body || empty(json_decode($this->getBodyString()))) {
         $this->setError(
           Helpers::replaceLinkTags(
             __('This is an empty email without any content and it cannot be sent. Please update [link]the email[/link].'),
@@ -342,6 +340,16 @@ class Newsletter extends Model {
     return SendingTask::getByNewsletterId($this->id);
   }
 
+  public function getBodyString(): string {
+    if (is_array($this->body)) {
+      return (string)json_encode($this->body);
+    }
+    if ($this->body === null) {
+      return '';
+    }
+    return $this->body;
+  }
+
   public function withSendingQueue() {
     $queue = $this->getQueue();
     if ($queue === false) {
diff --git a/tests/integration/Cron/Workers/SendingQueue/Tasks/NewsletterTest.php b/tests/integration/Cron/Workers/SendingQueue/Tasks/NewsletterTest.php
index 9f0de145c9..7b642db2e5 100644
--- a/tests/integration/Cron/Workers/SendingQueue/Tasks/NewsletterTest.php
+++ b/tests/integration/Cron/Workers/SendingQueue/Tasks/NewsletterTest.php
@@ -205,7 +205,7 @@ class NewsletterTest extends \MailPoetTest {
     $newsletter->type = Newsletter::TYPE_NOTIFICATION_HISTORY;
     $newsletter->parentId = $newsletter->id;
     // replace post id data tag with something else
-    $newsletter->body = str_replace('data-post-id', 'id', $newsletter->body);
+    $newsletter->body = str_replace('data-post-id', 'id', $newsletter->getBodyString());
     $newsletter->save();
     // returned result is false
     $result = $this->newsletterTask->preProcessNewsletter($this->newsletter, $this->queue);