Theatres have strict policies when you go to watch a play, a pop concert is totally different. You can find many videos filmed at theatre gigs, so I think it will be allowed.
From the tour, I don’t mind if she doesn’t dance as much, I don’t expect it either. I just hope she puts on a good show as she’s always done, good choreographies, good staging. Some jokes are ok, it would be amazing if she’ll speak to us a bit and interact with the public as we are in a theatre, but obviously I hope a lot of songs too and a good setlist. Length wise I’m a bit afraid it won’t be a long show as it states doors open at 20:30 for London. Theatres curfew is usually 23 and they won’t allow her to go any longer, so she must be on at 21 on the dot for a 2 hour show, but somehow I’m not seeing this happening :-/