It is mere speculation, but the potential solution, subject to SDR, would involve the army picking up the running costs for the domestic site and some kind of 2nd line engineering facility continuing, requiring the airfield to be opened from time to time.
The numbers being banded around for Lyneham"s infrastructure need are in the order or 115-125 mil. Considering that, according to my maths, the true spend involved at Brize is in the region of 400mil, Lyneham's bill doesn't seem too bad at all.
I have asked James if he would submit a PQ to ascertain the break even year for cost savings. Trouble is Rammell does not appear to want to include the housing costs in the move. Your estimate of 7mil is the lowest I have heard. The common figure I am hearing, once the station is closed, is a saving of 25mil per year, with an initial planned break even point in year 6. This seems like bolleaux to me, but if anyone else has the figures please pile into the debate.