diff --git a/src/Entity/EntitySubqueue.php b/src/Entity/EntitySubqueue.php
index 6c0a251..5cc5a6f 100644
--- a/src/Entity/EntitySubqueue.php
+++ b/src/Entity/EntitySubqueue.php
@@ -105,26 +105,28 @@ class EntitySubqueue extends EditorialContentEntityBase implements EntitySubqueu
 
     /** @var \Drupal\entityqueue\EntityQueueInterface $queue */
     $queue = $this->getQueue();
-    $max_size = $queue->getMaximumSize();
-
-    // Remove extra items from the front of the queue if the maximum size is
-    // exceeded.
-    $items = $this->get('items')->getValue();
-    if ($queue->getActAsQueue() && count($items) > $max_size) {
-      if ($queue->isReversed()) {
-        $items = array_slice($items, 0, $max_size);
+    if ($queue) {
+      $max_size = $queue->getMaximumSize();
+
+      // Remove extra items from the front of the queue if the maximum size is
+      // exceeded.
+      $items = $this->get('items')->getValue();
+      if ($queue->getActAsQueue() && count($items) > $max_size) {
+        if ($queue->isReversed()) {
+          $items = array_slice($items, 0, $max_size);
+        }
+        else {
+          $items = array_slice($items, -$max_size);
+        }
+
+        $this->set('items', $items);
       }
-      else {
-        $items = array_slice($items, -$max_size);
-      }
-
-      $this->set('items', $items);
-    }
 
-    // If no revision author has been set explicitly, make the subqueue owner
-    // the revision author.
-    if (!$this->getRevisionUser()) {
-      $this->setRevisionUserId($this->getOwnerId());
+      // If no revision author has been set explicitly, make the subqueue owner
+      // the revision author.
+      if (!$this->getRevisionUser()) {
+        $this->setRevisionUserId($this->getOwnerId());
+      }
     }
   }