N.J. Stat. § 43:16A-10.2: Adjustment to benefit.

5. The adjustment in the benefit to a surviving child or children made pursuant to the amendment of section 10 of P.L.1944, c.255 (C.43:16A-10) by P.L.2016, c.26 shall apply to a benefit entitlement initially granted on or after January 1, 2016, and, if granted on or after that date but before the effective date of P.L.2016, c.26, still in effect on that effective date. The adjustment in benefits to a surviving child or children pursuant to the amendment of section 10 of P.L.1944, c.255 (C.43:16A-10) by P.L.2016, c.26 shall apply only for benefit payments made after the effective date of P.L.2016, c.26. No surviving child of a deceased member of the retirement system shall be granted a retroactive payment based upon the difference between the benefit the person would have received if the adjustment made pursuant to the amendment of section 10 of P.L.1944, c.255 (C.43:16A-10) by P.L.2016, c.26 had been applicable at the date of entitlement and the benefit that the surviving child has received from the date of entitlement to the effective date of P.L.2016, c.26.

L.2016, c.26, s.5.