I would like to re-open this old thread which I have found why looking for the answer to the identical question.
I have Regional Control Officer in connection of possible unauthorised flight when a Wellington has landed at Honington after raid and shortly afterwards flew to East Wretham
So far my presumptions are:
1. this was and officer responsible for the air traffic so I would say something like present air traffic controller?
2. region means there was one for some area covering seveal airfileds?