Child support question..

So my husbands ex wife is wanting to change their custody agreement. Let me try to make this simple. We are in the state of Virginia. My husband pays $1,400 in child support and he gets them Saturday 6pm to Monday at 8am. (2 kids)

They go to court tomorrow to hopefully reduce it, well he randomly got a call from her saying I’m going to change the agreement to us getting them every other week, which wouldn’t work for us. We all have a job and she’s trying to switch her weekend job to a week job. Can my husband not agree to those terms if we literally can’t do it? He works until 8 at night, I also have 2 jobs where no one would be home. One isn’t even in school? Like can they just immediately change it?