On the operative date of this Charter, all offices, agencies and departments of the City and County then in existence under the Charter of 1932 shall continue to perform their functions, exercise their authority and fulfill their responsibilities, as they existed immediately before this Charter's becoming operative subject to the provisions of this Article. Not later than 90 days after the operative date of this Charter, each such office, agency and department for which this Charter does not provide shall cease to exist, and its functions, powers and duties shall be transferred to the appropriate governmental unit created by this Charter or under the authority of this Charter. The Board of Supervisors and the Mayor shall take all action necessary to provide for the orderly transfer of functions, authority and responsibility on or before the date of such transfer.