Employment Law Questions? Ask an Employment Lawyer.
Happy Thanksgiving and welcome to Just Answer.
I am very sorry to hear about this change in schedule. However, unless you have a contract which expressly restricts your employer's ability to do this, then I am afraid to tell you that they can. You can attempt to reason with your employer and explain that this is unfair and unprecedented. But ultimately they are free to manage their business and schedule their employees however they see fit. I am terribly sorry.
If I can clarify anything at all for you, please do not hesitate to ask. It is my pleasure to assist you further if necessary....