Finningly, QRA flights were generally against elint aircraft or naval tracking flights – occasionally a flight to Cuba or return (and USA every 4 years - 20 Jan), thus the Northern stations would have made sense.
However, the war threat was a more direct routing to the V bases / Cities over the N Sea. In later years aspects changed, some managed by tankers.
Phil, the Station Commander at Valley was always upset – regular MPCs. I recall a detachment to Valley to defend the RN with QRA / CAP. The staff and studes loved the spectacle of a scramble – more than 60 AOB in the circuit; Staich complained, the RN said it was for real – (Staish wasn’t a fighter pilot).
Lightning vs Hunter; very good sport, but when played for beers, always supersonic below 40K.
Lightning vs Buccaneer (RN) at low level (outside of the regs, but Boss said we were not to lose); turning and a large vertical component (yo-yo), about evens, particularly if the Buccs had Winders. But they never learnt about smoke trails or jet wake over water which made CAP easy.