In the event that the granting of a petition has become final, through failure to seek Administrative Review, by the final decision of a court on review if no further appeal is taken, or upon certification of election results in the event of a dissolution, the change in boundaries shall become effective the following July 1 . The school boards of the districts as they existed prior to the change shall exercise the same power and authority over such territory until such date, unless accelerated or postponed by stipulation of the school boards of each detaching or dissolving and annexing school district and approval by the regional board of school trustees with which the original petition is required to be filed.
105 ILCS 5/7-9