I called on Mrs Commandant at Catterick shortly after arriving, and went along with another newly arrived chap. They were RCs and had a big family and when we called we were given tea in the company of a couple of her under fives. Rather than the stiff "tea and cucumber sandwiches" occasion we were expecting it turned out to be a riot, which we thoroughly enjoyed. This was in 1965 and by the time I was posted to a new station in 1967 the practice appeared to have died out.
Re "ppc", when we were having a lecture on calling etc, the officer giving the lecture asked if anyone knew what "PPC" stood for. One of our number stuck his hand up and answered "pour prendre congé sir" (to take one's leave). The officer was a bit taken aback that someone had known, and I suspect marked the cadet down as a smart-arse.