10 ILCS 5/4-5

The registration preceding the November, 1942, election shall constitute a permanent registration subject to revision and alteration in the manner hereinafter provided; and all registrations subsequent thereto shall be upon registration record cards provided by the county clerk. However, if the county board, by resolution adopted before October 15, 1969, determines that there shall be a re-registration in the county before the June, 1970, primary as provided in this Article, such 1942 registration shall be a permanent registration only until such re-registration as provided in Section 4-5.01.