2A person designated as chairman or deputy chairman of a regional development agency shall hold office as such in accordance with the terms of his appointment unless and until—
(a)he resigns that office by giving notice to the Secretary of State, or
(b)he ceases to be a member,
and shall, on ceasing to be chairman or deputy chairman, be eligible for further designation as such in accordance with paragraph (a) or, as the case may be, paragraph (b) of section 2(4) at any time when he is a member.