Mich. Comp. Laws § 700.3612
Except as otherwise ordered in formal proceedings, the probate of a will after the appointment of a personal representative in intestacy or under a will that is superseded by formal probate of another will, or the vacation of an informal probate of a will after the appointment of the personal representative under that will, does not terminate the personal representative's appointment, although the personal representative's powers may be reduced as provided in section 3401. Termination occurs upon appointment in informal or formal appointment proceedings of a person entitled to appointment under the later assumption concerning testacy. If no request for new appointment is made within 28 days after expiration of time for appeal from the order in formal testacy proceedings, or from the informal probate, changing the assumption concerning testacy, the previously appointed personal representative upon request may be appointed personal representative under the subsequently probated will, or as in intestacy as the case may be.
MCL 700.3612