cyflier, if the Airmen's Rest Camp was indeed at 1BSD (which your pic seems to confirm) then the initials are pure co-incidence. 2ARC was in Morocco and 1BPD was in Algeria. Airmen in this case suggests other ranks, though including SNCOs it seems. Aircrew suggests Officers, Commissioned and Warrant, and SNCOs (Sergeants and above).
As to the CM for Low Flying, was that when he was collecting Giant Mushrooms?
Maybe it went to appeal? That would have slowed things up a bit.
The forced landing site seems to have given the person making the entry some trouble, let alone us! It could have been the name of a village, hamlet, or simply a farm! Intrigued about the White, and Black and White Flags. Don't remember those as part of the standard Signal Square. Is that where Black Flag comes from (ie no flying at all due wx)? An FTS thing?