Hello Karl!
Coincidentally, I have noticed that it does not or does not always display correct values in the "last change" column in https://www.thomas-ruf.ch/sitemap/. For example, I have completely revised the page www.thomas-ruf.ch/angebot/pilzkalender-2022 (gallery and content). Nevertheless, the date "Last change" is not updated.
What could be the reason for this?
Have a nice week and best regards from Basel
Thomas