Any views on the new pretty little liars book?

I'm not sure who the new A is but i think Alison's brother, Jason, definitely has something to do with it. I don't think he killed Ali or anything but it's kinda weird. I don't know but I suspect him to be part of it. Also yeah Jenna might also be A. She seems to be around a lot and she was in on the fire works thing with Ali so I think she has something to do with it too.