Cue five hours of random speculation on the Twitters in which most fans seemed to convince themselves that it would be a missing episode announcement or that Osgood was going to be announced as a companion or some such. Unless that was just me. Either way when this happened:
I am the creator & writer of a brand new, official Dr Who spinoff for television. It's called "Class", coming to your screens next autumn...— Patrick Ness (@Patrick_Ness) October 1, 2015
I HAVE MY OWN FREAKIN' TV SHOW! And it's a Doctor Who spinoff!!! Hands literally shaking...— Patrick Ness (@Patrick_Ness) October 1, 2015
BREAKING NEWS! We confirm a new #DoctorWho spin off: Class. From acclaimed author, @Patrick_Ness https://t.co/bfWKqgqv43 2016: 8 x 45 mins— Doctor Who Official (@bbcdoctorwho) October 1, 2015
Dear Doctor Who Announcements: please reserve the term 'big Doctor Who announcement' for found missing episodes only. Thanks.— Trevor Baxendale (@trevorbaxendale) October 1, 2015
"Meh, it's just a TV series based around Coal Hill School, who cares." Christ, I wish the Who fans of 1992 could see you now.— Eddie Robson (@EddieRobson) October 1, 2015
Which is entirely correct.
Anyway, so yes, a Doctor Who's getting a spin-off, it's called Class and it's set in Coal Hill School and it's written by Patrick Ness.
BUT and I've rather buried the headline here, the channel it's for, BBC Three, goes online only in January something which is unmentioned in the above press release (although the Radio Times has noticed). So when this is "broadcast" next autumn, it's main distribution point will be the iPlayer or a surviving BBC channel late night.
SO Class is, like Spooks: Code 9 before it, is a YA spin-off of a very successful existing property designed to promote the reformating of BBC Three.
Notice too that this is for BBC Three and not CBBC so although it seems like a rerun of SJA to some degree the tone they'll more like be searching for is Buffy or Almost Human but not, we should suspect Torchwood.
Speculation: the return of Courtney and Jenna Coleman as a series regular. Ian Chesterton cameo and Capaldi appearing in at least one episode.
Patrick Ness is supposed to be quite good. I wasn't a huge fan of his Puffin eBook from 2013 featuring Fifth and Nyssa, his only other Who credit so far, but you do have to ask why him? Are we seeing the BBC training someone to take over from Moffat? He only has one other screenwriting credit albeit on a major motion picture based on his own novel.
We don't know much about it but in general I'm still, well, hum. The Caretaker was the third worst episode of last year but that was mainly due to the appalling gender politics rather than anything to do with the school. But it doesn't feel like anything spectacularly new based on the press release, essentially Grange Hill with aliens and haven't we seen that already?
Which isn't to say that a Paternosters spin-off would be the better choice but there was certainly scope to introduce a thing in the main series, as per Torchwood, which was a bit more unusual. But the scope of this seems firmly based on what could be budgeted relatively cheaply as per most precinct dramas. I'll try not to pre-judge though. We await casting announcements with great interest.