We are going over a bit earlier, second week of May, we were in Arromanches the week before the 70th anniversary celebrations, place was packed, should be a great tribute.
Lots of road closures and restricted access on the days both sides of 6th June around the beaches so forgive me for stating the obvious but make sure your booked in where you want to be on the day or you may struggle to get close.
Adrian at Normandy Beach hotel is a great source of local intel, he does a lot of the event organising and supports a lot of vets.