Hi, I used a 100-400 like you but was blessed with better weather than on the Sunday. Shots were taken on a combination of either my 20d or 450d. Raptor was stunning and can’t wait to see it again.
I was there early. I arrived at the A15 gates at 7.00pm and was eventually let in at 7.45. Straight on to the statics before the crowds built up and the blue skies remained.
The aeropark museum at EMA sell old copies of Flypast etc for their funds. As it’s just down the road from you, I would think they might be interested in taking them off your hands.