Election times are specific for the actual day of election.  In these unprecedented times, early voting has opened up at least one month before election allowing people so much additional time to vote besides voting day.

There is no reason why accepting a mailed in vote without a postmark three days after the actual election as an "immaterial omission."  If the governor's office actually cares about preventing fraud and abuse, whereby a ballot can be stuffed based on the results publicized on election day, this regulation should not be enacted.