Methods, systems and devices for providing cardiac resynchronization therapy (CRT) to a patient using a leadless cardiac pacemaker (LCP) and an extracardiac device (ED). The system is configured to have available for use a plurality of modes for managing the timing of the CRT pacing delivery by the LCP acting in cooperation with the ED. The system is further configured to use various metrics to determine whether and when to switch from one of the CRT timing modes to another of the timing modes.