Any consolidation of regions, whether under Section 3A-3 or 3A-4, shall take effect at the expiration of the terms of office of the regional superintendents in office at the time the consolidation is approved under Section 3A-3 or directed under Section 3A-4. However, at the regular election immediately preceding the effective date of the consolidation at which regional superintendents are to be elected in accordance with the general election law, regional superintendents shall not be elected from each of the regions comprising the consolidated region, but one regional superintendent shall be elected to take office on the effective date of the consolidation.