My very first M.O.D. admin job was at HQ SW. I was 22 years old.
We were in charge of Quartering. Otherwise known as buildings in this vast area.
The buildings did not mean just quarters (soldiers’ houses) but also the nearby COIN & FIBS.
COIN – unless I’m retarding in my old age – stands for something to do with Counter Intelligence.
FIBUA is Fighting in Built Up Areas.
Or training in old knackered buildings that were once houses and shops and barracks etc.
Recycling old buildings usage HMForces style :o)