Whirly,
Maybe have a chat with your club management? My school charge brakes-off to brakes-on, unless there is a large ATC delay in which case they charge take-off to touch-down plus 10 minutes - could you convince them to do something like this? Came in very handy at the weekend when I was doing a 30-minute trial lesson and had to spend 20 minutes at the hold waiting for departure. (The student didn't mind at all, though, since the traffic we were holding for included a Spitfire and a Hurricane taking off in formation, and we had a perfect view!)
FFF
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