7(1)Immediately after a development plan has been approved or made or amended by the Secretary of State under this Schedule, the local planning authority shall publish, in such manner as may be prescribed, a notice stating that the plan has been approved, made or amended, as the case may be, and naming a place where a copy of the plan or of the plan as amended, may be seen at all reasonable hours, and shall serve a like notice—
(a)on any person who duly made an objection to, or representation with respect to, the proposed plan or amendment, and has sent to the local planning authority a request in writing to serve him with the notice required by this sub-paragraph, specifying an address for service ; and
(b)on such other persons (if any) as may be required by general or special directions given by the Secretary of State.
(2)Subject to the provisions of Part XII of this Act as to the validity of development plans and of amendments of such plans, a development plan, or an amendment of a development plan, shall become operative on the date on which the notice required by sub-paragraph (1) of this paragraph is first published.