(a) Wherever this subchapter prescribes the performance of a duty by any official or agency of the District of Columbia, such duty shall be performed by the Mayor of the District of Columbia or such officer, employee, or agency as the Mayor may delegate to perform the duty for him.
(b) Where any provision of this subchapter, or any amendment made by this subchapter, refers to an office or agency abolished by or under the authority of Reorganization Plan No. 5 of 1952, such reference shall be deemed to be to the office, agency, or officer exercising the functions of the office or agency so abolished.