633 was fiction, the RAF never had a sqn with that number. The army had and still has several sqns in the general series (some were glider towing units) in the Far East and others AOP units.
It is interesting to trace the sqn numbers still in use with some of our NATO allies and to find these started life as units operated from UK in the last war and often manned by Dutch, Norwegian and Danish crews. Many of the Canadian 400 series sqns started that way and 75 sqn was gifted to New Zealand at the war's end.
Lengthy story - but not now!!!
Old Duffer