§1. When the Roman Pontiff concludes a session of the synod of bishops, the function entrusted in it to the bishops and other members ceases.
§2. If the Apostolic See becomes vacant after a synod is convoked or during its celebration, the session of the synod and the function entrusted to its members are suspended by the law itself until the new Pontiff has decided to dissolve or continue the session.
Source: Code of Canon Law (Vatican.va)