The registrar shall keep safely and unopened all official presidential absentee ballots which are received subsequent to the election. Upon receipt of such ballot, the registrar shall write the day and hour of the receipt of the ballot on its envelope. All such absentee ballots returned to the registrar shall be safely kept unopened by the registrar for the period of time required for the preservation of ballots used in the election, and shall then, without being opened, be destroyed in like manner as the used ballots of the election. Such information shall be processed through the Statewide Election Management System.