If a vacancy shall occur in the elective office of the county superintendent of education elected at the November 2015 general election before January 1, 2019, the office of superintendent of school shall immediately become an appointed position, and such vacancy shall be filled by appointment by the county board of education. In such case the person so appointed by the county board of education shall hold office under the terms and for the duration of the employment contracted issued by the board of education under the authority of Section 37-9-25.