There's something about Bletchley Park in 'Watling Street', by John Higgs, which I've nearly finished reading. The codebreakers were mainly upper-class, and there is an anecdote about Admiral Louis Mountbatten, uncle of Prince Phillip and second cousin once removed of Madge, visiting it. As he walked into the main room, a young female codebreaker saw him and said "Hello, uncle Dickie! What are you doing here?". When the government wanted to sell it and move to Cheltenham after the war, they discovered, inconveniently, that they didn't actually own it.