Hi Laura and welcome to the forum. If they are a good employer and they have day shifts available, then it would be most likely to work. If they don't have day shifts available, then they might not want to keep you on nights since they could get into trouble for contributing to your ill health, and you could lose those shifts, potentially. It depends on what the law is like where you live, so I think others will be able to advise you about that. Good luck and I hope you are feeling better soon.