Mark has provided some excellent information which should assist you. You may wish to get a copy of the relevant pages of the War Diary as described in Mark's post "(W.D. 4 Cdn L.A.A. Regt., July 1944: Appx 10, "Activities of 32 Bty, D Day to D plus 6)"
If you are not in the Ottawa area there are several good (inexpensive) researchers who could request these documents and send you digital photos of them. I recommend Ken Joyce as one who knows his way around the archives. Just ask him to pull RG24, Volumes 14592, 14593, 14594 and 14595