Yeah, some rather frightening stuff there.
I think the footage at 3:56 is sliced from the attack which also appears from 4:26 onwards, which IIRC is off the Gironde estuary, in western France.
I also think WR-X is from 248 Squadron, before they headed north to Banff, in Scotland. "Mosquito Squadrons of the RAF" says WR is a code worn at one point by 248. Their first sortie from Banff was on 12 September, and there's a photo in Andy Bird's excellent "A Separate Little War", which shows a 248 Mossie with a DM code on the 19th of that month.
LR352, LR362, and LR363 are all listed by Air Britain as having been on 248 Squadron, and LR363 seems to have been X on 15 July. I suppose I'll have to download the Operations Record Book for 248 for July and August to be sure, though the ORBs can something of a minefield if one wants to tie up serials and squadron letters, as I'm finding out to my cost with the 23 Sqn docco.
Edit - The Imperial War Museum has a couple of useful photos.
Mass attack;
http://www.iwm.org.uk/collections/item/object/205023331WR codes:
http://www.iwm.org.uk/collections/item/object/205094133