Not that unusual. I'm a moderator/admin on a couple of forums and its normal practice to have a quarantine area to move threads for cleaning purposes.
Chuck the thread into a private area to either clear out the gash posts or delcide the fate of the whole thread.
Quite probably me. I've just moved ARRSE to another type of server. An attempt to find a way around the monstrous Amazon monthly bill we were facing. While it should be a transparent move and is near instantly reversible, the timing of your post coincides exactly with when I switched. Any more problems let me know please.