FC rotation system?

[Juha]

Hello, now and then it seems that not all remember that British system of fighter pilot rotation was different than that of USAAF. Maybe one of RAF specialists would like to write a short overview on British system.
IIRC sometimes in 1941 RAF established a rotation system. IIRC before that it was up to sqn CO, F/Lt, sqn MO or the pilot himself to suggest/order/ask reposting. IIRC one reason of the change of system was that some MOs complained to upper hierarchy that sometimes battle fatigue was noticed too late.
IIRC I have come across info that at least a couple RAF fighter pilots flew appr. 300 combat sorties, so I guess that those RAF/RAAF etc fighter pilots who achieved highest numbers flew more or less same number of combat sorties as those Finns (Juutilainen, Luukkanen ja Pyötsiä)who flew most, i.e. a bit under 450 combat sorties.

And I don’t know or at least cannot recall the number of combat sorties Johnnie Johnson flew. At least the number should be rather high. Can anybody help on this?

Juha