These two BSA owners are John Bangs and Fraser Mccallough. They had send me this photo to put on the visitors page but I have some problem with that pages and I am unable to up load photos there.
I am not really sure where they live to be honest, could be Australia???
At the peak of wartime production BSA made an M20 every ten minutes. So, they could have been as close as 5 hours apart (roughly) if they are mid to late war machines...Ian