This is a fascinating thread, and one that doesn't surprise me having had to negotiate with HIAL in my previous Job.
It beggars belief that since 1998 when the requirement for radar service provision was called for by the airlines operating to Inverness (primarily to deconflict with Mil ac) and was agreed to by the RAF,CAA, NATS and MOD, as an interim measure, that no progress has been made by HIAL to sort themselves out.
However, since then the amount of IFR GAT traffic going into Inverness has continually grown and grown.
As I understand it, come what may, the RAF will pull out of the Inverness task on 01 Apr 07. I don't blame them at all; the level of ac being worked now is far beyond what it was at the tasks conception and is likely to continue to grow, if recent press releases are anything to go by.