Aircrew promotions, leave cycles

[Hulluser]

Hello all, i am researching aircrew from Hull who were killed in bomber command during ww2. i am at present looking into some aircrew who all appeared to be on the same station Watton and 82 squadron during 1940. My main question is regards a leave cycle or something similar. i am assuming that aircrew were rostered for ops for a specific no of days then had a number of days off. i also am assuming that after approx 6 wks of duty they would be allowed 1 wk of leave. i think i have read this somewhere but can't find it again, i can't remember if this was for after 1942 for instance.
I have also read that aircrew aircraftsman etc were all promoted to Sergeants during May 1940, would anyone know the exact date?
Any help or thoughts would be much appreciated.
Regards

[PeteT]

The information I have suggests that it was agreed that Wireless Operators / Air Gunners and Air Gunners would be promoted to Temporary Sergeant with effect from 27th May 1940, but the order was not promulgated until 27th June 1940. [AMO A.416/1940 of 27 June].

[Source: ROYAL AIR FORCE HISTORICAL SOCIETY - JOURNAL 50]

[Hulluser]

Thank you Pete for the information, much appreciated.
Rgds