No doubt it was! This could happen after a serious problem or even after a system upgrade and/or plugins update on the server side. System plugins can randomly fail especially on old threads affecting some controls and reverting them to default state (ex: thread visibility visible/hidden, pinned/unpinned and its availability status locked/unlocked) In such situation, Mods don't get notifications about 'faulty' threads.
This probably is a restored thread after a lunatic hacked a sleeping admin account (a few years ago) and started deleting threads.