As far as i can tell, only your manager can put in or control the amount of hours you work in the week. I have my availability 6/7 days of the week, but since my manager knows i only work 15-20 hours they will schedule me for those hours.

Don’t overwork yourself, especially since you’re in school full time. I think your manager is in the wrong by coercing you to work more until trainees are at your store. I would talk to your manager again and really stick to your guns that you need less hours.

There was someone at mg store who was also in school full time and got scheduled too much. They talked to my manager often, but they didn’t change available hours. So my coworker quit. I don’t want that to happen to you, but please overwork yourself and potentially do poorly in school because of your hours! Best of luck!