Hi Tamjk,
As you mention D. F. O'Sullivan's service in the RAF in WW2. and that he was '
very much RAF in his way of doing things', you may already be aware; but best match in the London Gazette seems to be as follows:- 14th Jun 1944 - GENERAL DUTIES BRANCH Appointment to commission As Plt. Offs. on probation. (emergency): Flt Sgt [...] 1549408 Donal[?] Francis O'SULLIVAN (177841).
- 14th Dec 1944 - ROYAL AIR FORCE VOLUNTEER RESERVE. GENERAL DUTIES BRANCH. Confirmation and promotion. Plt. Offs. (probation.) confirmed. in appts. and to be Flg. Offs. (war substantive.): D. F. O'SULLIVAN (177841).
- 1st Sep 1945 - Award of Distinguished Flying Cross - Acting Flight Lieutenant Donald Francis O'SULLIVAN (177841), R.A.F.V.R., 78 Sqn.
- 14 Jun 1946 - Promotion. Flg. Off. to Flt. Lt. (war substantive.); D. F. O'SULLIVAN, D.F.C. (177841).
So the records above would suggest pre-commissioned service as a Sgt, then Flt Sgt, prior to 1944; and posted to 78 Sqn during 1945; therefore probably flying Dakota IVs from Cairo, as part of 216 Group of Transport Command, after the end of the war. Demobilization of RAFVR pilots following cessation of hostilities began in earnest in Aug 1945, and continued throughout 1946-7, which would tie in nicely with a move to BOAC post-war, IMO. I've yet to find a DFC citation though.
(for clarity - there is also a Desmond Francis O'SULLIVAN (151430) listed in the Gazette but he was killed in the crash of Lancaster LM127 into the North Sea on a raid to Kiel 27th Aug 1944 and buried in Esbjerg, Denmark )
Hope that's of help,
Squipdit Fashions.