Thank you for the information and your question. Unless you have a contract or a company policy that gives you more rights, then the employer is allowed to set the terms and conditions of employment, including when time off can be taken. Obviously if an employee takes a day of leave and will be gone the entire day they can schedule their appointment whenever they choose. However, when the employee is going to miss work time and the issue is not related to FMLA
time off for a serious health condition, then the employer can state when the hours are that the employee can take off, for whatever the reason. In fact, technically speaking an employer does not have to provide any time off, paid or unpaid, for non-FMLA qualifying illnesses or medical/dental issues. They must though, as I mentioned above, follow their own contracts or policies.
In terms of meal breaks, Michigan law does not requires employers to give any employees who are 18 years of age or older breaks of any kind, including meal breaks. However, if they do, and they don't pay for that time, the employee must not be allowed to work during that meal break. If they are, they must be paid for that time. The DOT rules would not affect this outcome.
Please let me know if you need any clarification. I would be glad to assist you further if I can.