Tenn. Code § 44-8-303
Any such agreement shall continue in force and be binding upon all the parties to the agreement and their heirs and devisees, for the period prescribed in the agreement, unless rescinded by mutual consent. The agreement may be modified or amended in writing signed by all the parties, at any time. After the expiration of the period prescribed, the agreement shall be deemed continued by unanimous consent, unless between November 1 and January 1, some party to the agreement or the party's heir or devisee gives notice in writing to all the other parties to the agreement, resident in the county, of the party's intention to terminate the agreement, in which event the agreement shall terminate at the expiration of ninety (90) days from the service of the notice.
T.C.A. § 44-8-303