1 November 1939 is notable in the 41 Squadron ORB for two reasons:

i. It appears to be the first date upon which the weather conditions are recorded on the F540 in World War II, after which such reports appeared on a daily basis; and

ii. Times of flights appeared on the F541, constituting the first proper appearance of the Form in the Squadron’s history. There are F541 entries for a combat on 17 October 1939, therefore pre-dating this entry, but this represented little more then an expanded account of what appeared on the F540 with timings, rather than the 'usual' list of pilots, aircraft serials and timings, as they do from this date forward. In fact, the F541 of 17 October does not list the aircraft serials or participants of the two airborne sections that day.

Was there therefore an order or formal change to procedures on this date, or did 41 Squadron possibly just get a bo##ocking from above and told to fill in the ORB properly?

Further, can anyone tell me when the F541 was formally introduced in the RAF, please?