The deal with Guflstream must be a good 'earner' and in itself must attract a lot of Gulfstreams to the location.
I believe the new FBO was seriously on the cards, but it became apparent that the lease on a large part of the ramp would expire some years after completion. So they would have been left with a lovely FBO but no-where to park any aeroplanes.
I think some very inventive ideas will be needed to get out of that one
Best thing would be to be out of that corner of the main ramp altogether and upfield in some wide open space. But then someone has to pay for all the infrastucture and suchlike. Oh, and LLA would probably say that you can have the land and spend £100m but they are only prepared to give a 6 year lease or something
Maybe I'm being cynical