Leave the staff tours for the young thrusters and allow the older non-thrusters to return to the cockpit. Gets my vote.
In the past, that's why we had Spec Aircrew! If you wanted to stay flying for a career, you became Spec Aircrew and gave up any thoughts of promotion. But it also avoided us having to polish chairs in Whitehall or work until midnight furthering someone else's career. I used to refer to Main Building as the 'Spec Aircrew recruiting centre' - one visit was enough to convince anyone teteering on a Spec Aircrew decision!
An ex-thruster at Sqn Ldr level reverting to Spec Aircrew Sqn Ldr could often cause some friction - such folk could have returned to the cockpit, but why should they continue to hold the rank?
Spec Aircrew was a bit of a weird system though - when they finally promoted me, I suddenly dound myself with more seniority than the Flt Cdrs...
Populating cockpits with ex-thrusters won't exactly do wonders for a sustainable manning plot - and doubtless would
seriously hack-off those poor souls waiting years to start flying training.