@rudi @veroandi "And: how can I reach them reliably if I really need to."If this helps at all, every Mastodon instance has a public email contact address on their "About" page. The instance software won't let it be activated without giving such an address.This is usually on a different provider to the instance itself, so it should work even if the instance is broken. If a user didn't make a note of the address, they can look at the archive.org version of the instance's About page.