diff --git a/mod/assign/upgradelib.php b/mod/assign/upgradelib.php
index 38e243d6f3e..d8bb7c2ca9e 100644
--- a/mod/assign/upgradelib.php
+++ b/mod/assign/upgradelib.php
@@ -143,6 +143,8 @@ class assign_upgrade_manager {
                     if (!$plugin->upgrade_settings($oldcontext, $oldassignment, $log)) {
                         $rollback = true;
                     }
+                } else {
+                    $plugin->disable();
                 }
             }
             foreach ($newassignment->get_feedback_plugins() as $plugin) {
@@ -151,6 +153,8 @@ class assign_upgrade_manager {
                     if (!$plugin->upgrade_settings($oldcontext, $oldassignment, $log)) {
                         $rollback = true;
                     }
+                } else {
+                    $plugin->disable();
                 }
             }