I'm planning to go there with a freind in his L4 (covering for his NPPL territorial restrictions). My research has not come across any airshows in Normandy for the event.
I went in 1984 when there was an excellent show at Caen. Reagan had just departed in the Nimitz from his brief visit, and there was no undue red tape. Pity they can't do the same again.
'Would be interested to know more about the L4 gathering though.