About this time of year, give or take a bit depending on weather and latitude that UK bats will start thinking about hibernating, give it a few more weeks and they'll be snoozing. Just be careful not to disturb them.
Maybe I'm overly paranoid but I don't take photos of them or mention them on forums! for fear of being labelled a bat botherer. "recklessly disturbing a bat at roost" in England and Wales can get you a £5k fine + £5k per bat if more than one. Realistically you have to be starting fires or setting off fireworks at them or something deservingly stupid to get that fine, but best not temp fate though.