I fully understand that the ridiculous overstretch and undermanning of today's RAF cause considerable turbulence - but, apart from during my UAS QFI tour, I certainly couldn't guarantee to be able to book ahead for anything unless it coincided with a period of approved annual leave.
I do think, though, that a quick-access 'availability' overview would be helpful for those wishing to book a room.
Perhaps a number of rooms should be kept 'free' for current serving officers only - but with a cut-off after which they could be made generally available? For example, 10 rooms could not be booked by anyone except current serving officers until the week beforehand? The numbers of rooms and days beforehand might need tweaking, but as a general concept??