13-A. Partial Termination. Unless the Parties agree otherwise, the Airline Parties may jointly terminate the provisions of Sections 4-D (Domiciles), 7-A (Furlough with regard to United Pilots only), 7-C (Flying Ratios), 7-D (Domicile and Base Protection), and 9 (ALPA Travel), individually or collectively, at any time on or after December 31, 2011, if the parties have not reached a tentative agreement on a JCBA by that date.