The election of county and precinct officers shall be held on the Tuesday next following the first Monday in November, 1922; and every four years thereafter on the Tuesday next following the first Monday in November, and all such elective county and precinct officers shall after midnight, June 11, 1919, be elected at the time herein specified: PROVIDED, That if a vacancy occur during the first biennium after any such election, an election to fill such vacancy for the unexpired term shall be held at the next succeeding general election.