However, it is possible that Flash's relative was promoted to Rear Admiral so that he could undertake some work for the Admiralty
Interesting point that. A friend of mine retired from the RAF as a Flight Lieutenant. Some time after that he was approached as a possibility for some consultancy work. He said the odd thing about it was that when he was talking to someone about it the bloke talking to him consistently referred to him as 'Squadron Leader'. He just assumed the records had been cocked-up but reading the above I wonder if he would have got a belated promotion for the same sort of reason.