N.J. Stat. § 18A:6-31.4
Whenever a new school district is created, the terms and conditions of employment, whether established through a collective bargaining agreement or past practice, of the largest constituent school district which is affected, replaced or displaced by, or forms part of the new school district, shall apply until a successor agreement is negotiated with the majority representative of the new school district. As used in this section, the term largest constituent school district means that school district which employs the largest number of teaching staff members.
In the event that there is an employee bargaining unit in a constituent school district with the next largest number of employees and with a majority representative of the unit, which is not so represented in the largest school district, the terms and conditions of employment for all employees holding positions in that unit in the new school district shall apply provided that the terms and conditions of employment shall only apply to the new school district's employees in that bargaining unit.
N.J.S. § 18A:6-31.4