Mich. Comp. Laws § 500.2418
If at any time after approval of any filing either by act or order of the commissioner or by operation of law, or before approval of a filing made by a worker's compensation insurer controlled by a nonprofit health care corporation operating pursuant to the nonprofit health care corporation reform act, 1980 PA 350, MCL 550.1101 to 550.1704, the commissioner finds that a filing does not meet the requirements of this chapter, the commissioner shall, after a hearing held upon not less than 10 days' written notice, specifying the matters to be considered at the hearing, to every insurer and rating organization that made the filing, issue an order specifying in what respects the commissioner finds that the filing fails to meet the requirements of this chapter, and stating for a filing that has gone into effect when, within a reasonable period thereafter, that filing shall be considered no longer effective. A copy of the order shall be sent to every insurer and rating organization subject to the order. The order shall not affect any contract or policy made or issued before the date the filing becomes ineffective as indicated in the commissioner's order.
MCL 500.2418