N.J. Stat. Ann. § 34:13A-5.8

Payment of the representation fee in lieu of dues shall be made to the majority representative during the term of the collective negotiation agreement affecting such nonmember employees and during the period, if any, between successive agreements so providing, on or after, but in no case sooner than the thirtieth day following the beginning of an employee's employment in a position included in the appropriate negotiations unit, and the tenth day following reentry into the appropriate unit for employees who previously served in a position included in the appropriate unit who continued in the employ of the public employer in an excluded position and individuals being reemployed in such unit from a reemployment list. For the purposes of this section, individuals employed on a 10-month basis or who are reappointed from year to year shall be considered to be in continuous employment.