Michigan Compiled Laws, Chapter 421. Employment Security § 421.49

Sec. 49.(1) When the last day of the 30-day protest or appeal period, as provided for in this act, falls on a Saturday, Sunday, or legal holiday, the 30-day period shall run until the end of the next day which is not a Saturday, Sunday, nor legal holiday.

(2) The 30-day protest or appeal period after the mailing of a notice of determination or redetermination as provided in sections 14 and 32a  1 and the 1-year period from the date of mailing of the original determination as provided in section 32a shall begin to run from either the date of mailing or from the date of personal service of the determination or redetermination.