Thank you all for your help, I kept researching in my books and in the book I talked about in
post #13, it seems that the only missions in the night of 5/6 June 1944 was to support invasion (maybe as an escort), it seems that the first flight with MM629 was on night 14/15 June to protect South-East of England against German night bombers coming from over Belgium. The missions against V-1 attacks were over South-East of England too. It seems that from September, all victories claimed with MM629 were over German territory...
So to resume, ifs I well understood (English language isn't my maternal language): in the few photos of 85 Sqn Mosquitos dated fom second half 1944 , none with IS, the only mission to support invasion was the night of 5/6 June 1944, all other missions were defence of the English coasts and night missions over German territory. It is said in the book that only the aircrafts which participed to the invasion in Normandy and over France wore the invasion stripes, it seems that is not the case of 85 Sqn.
So I think to keep my opinion as stated in
post #11 => no D-Day stripes for MM629.
I hope it's the right decision