would turn up as you say, in a mix and match.
When I was working in HQ BFFI (after the war) - '86-'87 I guess - we had a visit from the RAF Staff College from Bracknell.
Their "combat kit" (their words) was as follows:
DPM trousers, DMS boots and puttees(!)
Blue shirts, ties and (blue) woolly pullies
DPM jackets
SD hats.
I had enough trouble keeping a straight face, Lord knows what the RN and Army thought of it.......