As usual, no-one seems to know anything, that picture was taken in an empty apartment, that fan may not be original, could have been fitted by a handyman or anything I suppose. All I know is it is supplied by a 3C&E via a spur with a 1 gang switch at worktop height. Most that are wired like this have a boost switch above the worktop but stupidly I forgot to look what the switching arrangement was and the job is about 30 miles away.
It was the same story with the power, apartment dead, found the plant room, someone had switched the isolator off, switched on and still no power so I thought they must have removed the fuse as well. found a fuse in the van, took the cover off and the fuse carrier was missing as well. No-one knows where the carrier is and no-one knows who turned the power off, building is quite new as well but as always no-one is interested. So I did my bit and went home.