(1) The Board may co-opt persons not exceeding five as extraordinary members for any special proposer 1[Members other than Ex officio and co-opted members, shall hold office for a term of five years from the date of the notification under Section 5].

(2) The term of office of co-opted members shall terminate on completion of one year from the date of co-option.

(3) 2[* * *]

(4) When the term of office of members other than Ex officio members has expired, the vacancies so arising shall be filled as soon as may be, and to this and all necessary steps shall be taken by the Secretary of the Board within three months before the expiry of the said term of office:

Provided that the term of office of the outgoing members shall be deemed to extend to and expire with the date on which the names of their successors elected or nominated, as the case may be, are notified under Section 5.