(1) In the event of occurrence of any vacancy in the office of the Chairman by reason of his death, resignation or otherwise, the seniormost Member shall act as Chairman until the date on which a new Chairman, appointed in accordance with the provisions of this Act to fill such vacancy, enters upon his office.
     (2) When the Chairman is unable to discharge his functions owing to his absence, illness or any other cause, the seniormost Member shall discharge the functions of the Chairman until the date on which the Chairman resumes his office.