Shops in big towns and cities always get cleaned in the dark the shop fronts are illuminated it’s in a lot of cases easier to see if you’ve done a good job,a lot of the time if you see the windows being cleaned at 8-9am they been there a good 2-3 hours.
I know someone that cleans shops from 10-30am till 4 buckets in the way of shoppers etc lots of people about,can’t think of anything worse,most shops are a nightmare these days they used to be the holy grail of window cleaning these days I find them a pain.