The great things about Duxford is the runway length and access to the museum (and facilities).
Flying Legends is a long day - last time I launched at 10:00 to arrive for a 12:00 slot, spent a very hot day on the airfield, launched again at 18:40 arriving back at home airfield at 20:30 and in the pub by 21:15.
if it goes anywhere it has to be at a centrally-located airfield, with massive parking and hangars with interesting aircraft (for when it rains or is too hot)
Duxford is perfect - though a slog from the SW - so I really hope a solution can be found to stay at Duxford.
My favoured alternative would be Fairford or Kemble. Or Newquay