diff --git a/mailpoet/lib/Entities/ScheduledTaskEntity.php b/mailpoet/lib/Entities/ScheduledTaskEntity.php
index 305571106b..6ef5acd61f 100644
--- a/mailpoet/lib/Entities/ScheduledTaskEntity.php
+++ b/mailpoet/lib/Entities/ScheduledTaskEntity.php
@@ -21,6 +21,7 @@ class ScheduledTaskEntity {
   const STATUS_PAUSED = 'paused';
   const STATUS_INVALID = 'invalid';
   const VIRTUAL_STATUS_RUNNING = 'running'; // For historical reasons this is stored as null in DB
+  const TYPE_SENDING = 'sending';
   const PRIORITY_HIGH = 1;
   const PRIORITY_MEDIUM = 5;
   const PRIORITY_LOW = 10;