The answer to this question depends on whether or not you're talking about liquor stores in Michigan. According to the state government, it's illegal for retail establishments (except grocery stores) to sell alcohol products between 2 am and 7 am. Bars and restaurants are also prohibited from selling alcohol within that time frame but reserve the right to serve by acquiring a Class C Liquor license which allows them to open at a later time.
Michigan residents who feel some need for another drink before 7 am should look up local bars or hotels where they can order drinks during those hours.
If you're referring specifically to liquor stores in Michigan, state law prohibits the sale of any alcoholic beverages between 2 am and 7 am.