Great Tit behavior

I have been seeing a Great Tit roosting (?) in an empty nest box for the last few days - it usually just enters early evening and settles down, close to one side. It may be taking seeds in from a nearby feeder, but no very often.

It's not taking nesting material in, which isn't surprising at this time of year. But could it be confused by the recent warm spell?

Is this sort of behavior unusual?