It's years since I last flew at Halton (since the Ridgerunners went bust in '97) but in those days, the airfield was mainly funded by Headquarters Air Cadets for 613 VGS (and for a short period 612 VGS), hence the VGS always had first call on use of the airfield, but others could use it when the VGS was not operating. Since then, the RAFGSA centre has moved in from Bicester, so it's busier on weekdays, but as far as I know the following still applies:
When the VGS is in operation, ALL non-VGS traffic whether powered or otherwise MUST use the gliding strip NOT the marked runways.
Ops Man R.D.?