Mich. Comp. Laws § 168.351

Sec. 351. After the filing of a nominating petition or filing fee by or on behalf of a proposed candidate for a township office, the candidate is not permitted to withdraw unless a written notice of withdrawal is served on the township clerk not later than 4 p.m. of the third day after the last day for filing nominating petitions or a filing fee as provided in this act, unless the third day falls on a Saturday, Sunday, or legal holiday, in which case the notice of withdrawal may be served on the clerk up to 4 p.m. on the next secular day.