One of the bee species that can be found in the bee hotels on days when the weather is less fortunate or at sundown / sunrise, is the European wool carder bee (Anthidium manicatum).
The bee doesn’t nest in the hotel but uses is as cover to sit out colder and wetter days, or as sleeping place to spend the night. Apparently the bees do not like the crowdedness of the hotel’s other guests and prefer to nest in quiet hidden tunnels elsewhere1. The bee will position itself with the abdomen and pointing towards the exit.
References1 Breugel, P. van 2014. Gasten van bijenhotels. – EIS Kenniscentrum Insecten en andere ongewervelden & Naturalis Biodiversity Center, Leiden.