Sec. 8152. (1) The eighty-seventh-A district consists of the county of Otsego, is a district of the first class, and has the following number of judges: (a) Until the date determined under subdivision (b), this district has 1 judge. (b) Beginning on the date on which a vacancy occurs in the office of district judge in the eighty-seventh-A district or the beginning date of the term for which the incumbent district judge in the eighty-seventh-A district no longer seeks election or reelection to that office, whichever is earlier, the eighty-seventh-A district consists of the county of Otsego and is a district of the first class. Under section 810a, the probate judge for the county of Otsego shall serve as judge of the eighty-seventh-A district. (2) The eighty-seventh-B district consists of the county of Kalkaska and is a district of the first class. Under section 810a, the Kalkaska county probate judge shall serve as judge of the eighty-seventh-B district. (3) The eighty-seventh-C district consists of the county of Crawford and is a district of the first class. Under section 810a, the Crawford county probate judge shall serve as judge of the eighty-seventh-C district.