Mich. Comp. Laws § 400.111n: Effective date of policy changes affecting Medicaid cost reports.

Sec. 111n.

Except as otherwise provided in this section, if the department issues a new interpretation of existing Medicaid provider policy directly affecting nursing facility Medicaid cost reports, that change in policy must have a prospective effective date. A policy may have a retrospective effective date as part of a state plan amendment approval or waiver approval, or if required by state law, federal law, or judicial ruling.