I came across a little colony of these on the moors. A few of them seem to have shut up shop and covered their entrances but there were still a couple around - maybe hibernating?
This one went into his hole and them came right back out again.
No time to look up their behaviour at the moment. Maybe more detail later.
UPDATE: with a little research, I think this is a Common Colletes it fits the description of it being on a south facing bank with a smartly and thinly striped white butt.