Edits
I've managed to get a /vanilla/ server running. That's it so far, though.
The server updates automatically again. I'll try updating sourcemod soon.
Sourcemod works again! \o/
ValvE has finally decided to drop the HLDS update tool. Hurrahs all around.
..or not. We're stuck using the horrifically bad SteamCMD tool. As of this post it's refusing to update the server, so I've got a lot of things to look into.
That means that the TF2 server will be down for a little while.
If anyone has any ideas how the hell this thing works, please let me know.
And don't link me to the wiki page with the instructions for setting up a server with it. I've read that already.
Thanks, and apologies for the inconvenience.