A man after midnight

The Pissemoff site office is the usual set of containers with two levels, outside stairs, steel door, a couple of windows and chintz curtains. It sits about a hundred yards from my foxhole and I've noticed that for the last few months they have been leaving the light on randomly (like my children do)
As part of my observational log I had been recording when the light was left on and when off. There appeared to be a pattern but it took me a while to work out that it was actually morse code. Three alternate nights on, then three alternate weeks on, then three alternate nights on, repeated - wasn't that the same message sent from the Titanic?
I now wonder which one of the fluorescent green clad muppets is the ABBA fan.

Disclaimer: This story is satire,  this means it is for entertainment only and is not true apart from the lights randomly being left on. Mr Anthrop accepts no responsibility for the accuracy or otherwise of this information - it is all untrue. If you are a house developer reading this , well done!