I think you must have been told either by word of mouth or notices on the doers of the facilities blocks what time they are cleaned

As most site staff will say "members never seem to know when the facilities are closed for cleaning ,but they always are in a queue when they think they should be open

And as site staff say we clean to a standard not a timetable and at busy times the state that the facilities are in may well mean a later opening

And it is not a legal requirement for a site to have any facilities as those staying normally have their own. In their LVs