Mich. Admin. Code R. 421.605
Rule 5. If a reimbursing employer complies with the security requirement of R 421.601 to R 421.603, but is delinquent in making reimbursement payments for 2 consecutive quarters after the imposition of the security requirement, or if the delinquency is at any time more than the amount of security required, the commission shall terminate the employer's reimbursement status as of the beginning of the next calendar year. For the purpose of termination of reimbursing status, an employer shall be considered delinquent if a billed amount is not paid within 30 days of the due date of a charge or billing. If the billed amount due is for benefit charges that have been protested by an employer and are under appeal, the employer shall pay the benefit charges, under protest, to avoid termination as a reimbursing employer.
Mich. Admin. Code R. 421.605