If within the bureau of a territorial chamber of commerce and industry the positions of president, vice-president, treasurer and deputy treasurer are vacant, the supervisory authority shall ensure the expedition of current business until the election of a new bureau. In the event of a vacancy in all the offices within the bureau of a local or departmental chamber of commerce and industry in the Ile-de-France region, the bureau of the regional chamber of commerce and industry shall ensure the dispatch of current business. During the term of office, the president of the territorial chamber of commerce and industry may propose to the general meeting to modify the composition of the bureau, or to replace some of its members in addition to the ex officio members provided for in article R. 711-21 and up to half of the members of the Bureau.