24 Pa. Stat. § 2-226
If any new school district is made by the creation of any city, borough, township, or independent school district, or by the annexation of territory comprising a separate school district to a city, or borough, or township, or if the boundary lines of any school district are changed, by reason of the changing of the boundary lines of any city, incorporated town, borough, township, or independent school district, then, in any such case, the change, so far as it relates to school districts or school affairs, shall take effect at the beginning of the first school year after such new city, borough, township or independent school district has been created, or such annexation effected, or such change in boundary lines permanently effected.
24 P.S. § 2-226