The office of a member of the Listing Committee shall be vacated if any one of the following events occurs:—
(1) if a receiving order is made against him or he makes any arrangement or composition with his creditors;
(2) if he becomes insane or is found to be of unsound mind within the meaning of the Mental Health Ordinance (Cap. 136);
(3) if by notice in writing to the Board and the Listing Committee, he resigns from his office; or
(4) if by reason of serious misconduct he is removed by the Board and a written statement setting out the reasons for his removal has been delivered to the Commission,
provided that the acts of such member shall nevertheless be treated as valid and effectual in all respects up to and until an entry of the vacation of office shall be entered in the minutes of the Listing Committee.