I work on an assembly line, we haven't been meeting our quotas due to machine failures. Management has the bright idea to implement mandatory overtime. Our normal shift is 3pm-11pm Monday through Friday. They want to extend it to 3pm-1am Monday through Thursday and an 8 hour day on Friday for a 48 hour week. I have a contract that I signed before starting employment, it guaranteed certain works terms like the working hours and pay scale. The contract does not guarantee me to a certain length or term of employment. I live in Colorado, an “at will” work state. Do I have any legal recourse to not perform the overtime or otherwise?