N.J. Stat. § 54:5-114.5
The governing body on good cause shown shall have the power to extend the time and to grant further extension or extensions of time within which the final decree or judgment must be recorded as hereinabove described; provided that an application for such extension, further extension or extensions of time shall be made to the governing body, before the expiration of the 2-year period or the expiration date or dates of said further extension or extensions as hereinabove provided.
If the final decree or judgment shall not have been recorded within 2 years from the date of the confirmation of the sale, or on the expiration of the extended time or times, then the sale shall be null and void, and the right, title and interest of the purchaser shall cease and revert to the municipality.
As to all sales of tax sale certificates made prior to July 3, 1956, under this act, where the final decree or judgment was not or has not been filed within 2 years from the date of the confirmation of the sale, or within the time limited by any extension or extensions theretofore granted, the governing body, on good cause shown, shall have the power to extend the time within which the final decree or judgment must be recorded; provided, that the first application for such extension shall be made to the governing body within 2 years after July 3, 1965, and in the event that such application is made within said time and is granted by said governing body said final decree or judgment and the sale, right, title and interest of the purchaser in the tax sale certificate shall be valid, anything contained in this act to the contrary notwithstanding.
N.J.S. § 54:5-114.5