diff --git a/.github/workflows/gradual-strict-null-checks.yml b/.github/workflows/gradual-strict-null-checks.yml
index 5cefb7700c..c90023aae6 100644
--- a/.github/workflows/gradual-strict-null-checks.yml
+++ b/.github/workflows/gradual-strict-null-checks.yml
@@ -1,7 +1,7 @@
 name: Lower null checks
 
 on:
-  pull_request:
+  workflow_dispatch:
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}