Is there another bathroom available? Bc if not, they might just be trying to do what they can with their schedule. If there are other bathrooms on that floor, they’re being rude. Just say no, and that you have to clean. If someone goes to the bathroom, tell them that you’re cleaning and you need it to be empty, and ask them to not to do it again. Usually women that age won’t tell a male staff member no. They’ll be sheepish and talk to their friends about it after they scurry off
Okay, I understand how it’s uncomfortable for you. That’s completely logical. But if there’s one bathroom, these girls are probably just showering when they have the time to, and the RA probably just really needed to use the restroom. This seems like more of a structural issue, because it’s hard to tell people to just…be dirty if they don’t have the time to shower later or to just piss themselves if they have to use the restroom.
You’re good, but yeah, tell them to leave. Just say the area is closed for cleaning. After a few times, the incidents should go down as people understand the rules. I’m also not sure if this is a majority-freshman dorm where there’s a lot of girls who don’t know the social rules around college yet. Then again, I have some freshman in my building, and I’ve never seen anyone go into a bathroom that’s getting cleaned. But still.