this video about training of motorcycle dispatch riders in 1944. None of the most visible motorcycles are Royal Enfields, though the one at 13:06 (shown in the picture, you can also see it at 13:18 where the Burman gearbox is visible) could potentially be a WD/CO.
This is what Wentworth Woodhouse in Yorkshire looks like today. It has an interesting history.
The Motorcycling Du Ponts
17 hours ago