Presence fob, extra values

I am always messing with presence as my cell is never really reliable; I pair it with a fob and a piston.
The piston has been erractic and I am wondering if it due to the new values of “occupied” and “unoccupied” which are not part of the WebCore lexicon.
Why has ST included these 2 new item without mention of their use?
I left home today for 2 hours and my cell went to “unoccupied” instead of “departed” which is what my code wants to see.

The ‘occupied’ and ‘unoccupied’ values are for the ‘occupancy’ attribute of the Occupancy Sensor capability. They’ve been part of mobile presence for over two years now, though I’m not sure it has ever been established what they actually mean in practice.

They should be completely separate to the ‘presence’ attribute values though.

Yes, I have seem them there before. I would like to know what makes a presence sensor aquire that value and stay there. This is most likely part of the reason cell phones are unreliable, they go “unoccupied” and not “departed” so the logic fails.