diff --git a/.github/RELEASE_NOTES.template.md b/.github/RELEASE_NOTES.template.md
index 4a01ccc2..b99e3a30 100644
--- a/.github/RELEASE_NOTES.template.md
+++ b/.github/RELEASE_NOTES.template.md
@@ -10,6 +10,14 @@
 
 ### Cookiecutter template
 
+All upgrading should be done via the migration script or regenerating the templates.
+
+```bash
+curl -sSL https://raw.githubusercontent.com/frequenz-floss/frequenz-repo-config-python/v0.12/cookiecutter/migrate.py | python3
+```
+
+But you might still need to adapt your code:
+
 <!-- Here upgrade steps for cookiecutter specifically -->
 
 ## New Features
diff --git a/cookiecutter/migrate.py b/cookiecutter/migrate.py
index de0f83ae..282adeba 100644
--- a/cookiecutter/migrate.py
+++ b/cookiecutter/migrate.py
@@ -42,7 +42,7 @@ def add_default_pytest_options() -> None:
     pyproject_toml_content = pyproject_toml.read_text(encoding="utf-8")
     marker = "[tool.pytest.ini_options]\n"
     new_options = (
-        "-W=all Werror -Wdefault::DeprecationWarning "
+        "-W=all -Werror -Wdefault::DeprecationWarning "
         "-Wdefault::PendingDeprecationWarning -vv"
     )