You can only request an availability change and the your manager has to approve it. Sounds like you have a shitty SM.

It’s a request. Your sm has the option of approving it or denying it. If that’s change drops them under a certain amount of coverage for a day or day part they need to hire. Hiring a new partner to cover one under covered 4 hour block means the rest of that partners hours come from somewhere and everyone is reduced in hours.

Approving the new availability also would allow a Sm to drastically change the number of hours you work and because it is due to your availability you won’t be able to fight it with the company or unemployment.

Did you ask them if there is a certain day that is worrying them? Or if you dropped it to more limited that your aware that your hours will reduce and your okay with that?

They attitude isn’t okay, but some level of prying might be.