The authority shall prepare and publish a report under section 74(3) of the Act within 12 months of the date on which the designation was made.

Where the measures to be implemented for securing the purpose or purposes for which the designation was made have not been completed within 12 months the authority shall, in addition to preparing and publishing a report under paragraph (1), prepare and publish further reports under section 74(3) of the Act, at intervals of not more than 12 months until the said measures have been completed.