N.J. Stat. § 48:2-31: Balance of reserve; disposition

If the work called for by the contract mentioned in section 48:2-30 of this title is not completed during the fiscal year in which the contract is made, the balance of the sum reserved by the comptroller on account of the contract shall remain to the credit of the board and shall be used for the purpose of making further payments until the work called for by the contract is completed. No such balance shall be retained nor shall any such contract be extended beyond the close of the fiscal year following the year in which the contract is made.