This is a UI bug on the App Engine side and should not be a concern since no versions are actually affected.

This happens when you:

• Recently deleted the default version.

• Recently upgraded from the legacy runtime version.

The server is still reading the internal information, which is causing a difference in the UI and rendering the warning message "End of support runtimes” and should be automatically refreshed after a week.

Since this was observed 10 days ago, is it still showing the error? If so, you can file an issue against the App Engine team so they can provide detailed troubleshooting.