Opinions sought on boot sale find…

Hi all;

Just wanted to seek a few opinions on an item I picked up at a boot sale yesterday here in Somerset. It was bought from a house clearance woman that I buy a few bits from regularly for the princely sum of 50p from a box of assorted old paperwork. As you can see, nothing out of the ordinary…

However, on looking inside the front cover, I found this inscribed in blue ink…

Interesting! Not sure if it is genuine at all as I’m not all that up on old HMSO publications. Would Guy Gibson need a copy of Elementary Flying Training?? Not sure who Sqdn Ldr Rawlings is either in connection with 617. Anyone have any thoughts…is it some sort of later facsimile re-print? It looks old enough and it does appear to be ink as opposed to being printed.

Any thoughts from the experts?

Thanks in advance!

Best regards;
Steve