I hope this sides with the employee, and the Court sets down standards not related to religion on when it's appropriate to change schedules.
When I worked at Scamway (contractor W2), they would routinely use schedule changes as a way to retaliate against employees,l; or, in just to get them to quit. They were especially hard on their full-time direct employees, because they wanted them to resign and lose future pension deposits and dump the high health care cost.
Anyway you tear it, a win against an employer is a win for us all. Even if you don't follow Sky Daddy, per se.