According to the BBC local news at 1830, Marshall have said they will not be relocating to Mildenhall. The base is set to close in 4 to 5 years. All this is subject to Congressional approval.
Two F35 squadrons will move in to Lakenheath. However, they didn't say if some of the F15's currently there would leave. I'd suggest that the '15C fighters would go and be replaced by the '35's, plus another squadron, making a net 'increase' of one squadron. This would bring the 48FW up to the four squadron establishment it had a few years ago.
I suspect there will be a big surge in double glazing in Brandon, as the F35 is alleged to be a very noisy beast.......
All or part of the units at Alconbury will move to 'a base in Oxfordshire' (Croughton)??
As always, guesses are ten a penny this early on......