For 1994 through 1996, a school district may levy, in addition to the millage authorized under section 1211, not more than 3 additional mills for enhancing operating revenue if approved by the school electors at an election held after 1993. The question of levying mills authorized under this section shall be presented to school electors as a separate question and identified as being for enhancement of operating revenue. A school district that is not a school district described in section 20(12) or (13) of the state school aid act of 1979, being section 388.1620 of the Michigan Compiled Laws, shall not levy any millage under this section that was approved by the school electors after September 30, 1994, unless the school district levies, for the same tax year, the maximum number of mills under section 1211 that does not exceed the limitations imposed by section 1211(3).