There's only one studio at Bristol and one main gallery. There's a small gallery used for breakfast but it's technical abilities are limited afaik. While Southampton do have two studios and two galleries (the breakfast gallery does have a sound desk and can handle lives, Chroma Keys etc) Studio B is not normally rigged or lit. They would need to borrow at least one camera from Studio A at the very least. Last time two programmes were broadcast at the same time from Southampton, was when Oxford's gallery was rebuilt a couple of years ago. The presenter and cameras remained in Oxford however, so Studio B's floor wasn't used. It was quite complicated getting it to air circuits wise!
Everyone here seems to assume that all you need to put out a programme is a studio. That's the least of your worries. You need a set. You need stagehands to assemble it. You need to light it. You need a complement of cameras. You need to roster a crew. You need a director/vision mixer. And of course presenters. Sufficient ENPS terminals. An editor/producer. Journalists on site. Not to mention proper feeds to the multiplex. In an emergency, you can't just magic all these things out of thin air!!
Watching the 1.30 Spotlight back, it looks to be CSO, so presumably it's Bristol's DTL position and their second gallery being used to do it live, while Studio A and it gallery do Points West. Be interesting to see what 6.30 brings.
Interesting that the Channel Islands are getting Points West rather than Spotlight. I think I'm right in saying that they are pretty reliant on Plymouth to get on air, but it's strange that Coding and Mux haven't switched Spotlight into the Channel Islands feed.
Presumably the simple wipes within the Spotlight headlines sequence are a result of using a less complex vision mixer than usual.