This section and the amendment to Section 6 of Article VII revising the just value determination for the additional ad valorem tax exemption for persons age sixty-five or older shall take effect January 1, 2017, following approval by the electors, and shall operate retroactively to January 1, 2013, for any person who received the exemption under paragraph (2) of Section 6(d) of Article VII before January 1, 2017.