diff --git a/workbench_access.post_update.php b/workbench_access.post_update.php
index 0ba9043..243c16c 100644
--- a/workbench_access.post_update.php
+++ b/workbench_access.post_update.php
@@ -41,6 +41,11 @@ function workbench_access_post_update_convert_to_scheme() {
       'bundles' => array_keys($config->get('fields')['node']),
     ];
   }
+  // Let other modules intervene for additional types.
+  $this->moduleHandler->alter('workbench_access_scheme_update', $settings);
+  if (empty($settings)) {
+    throw new UpdateException('No schema configured. You should disable Workbench Access.');
+  }
   $scheme = AccessScheme::create([
     'id' => 'default',
     'label' => $config->get('label'),