2. The said documents shall be made available not later than the date of the first publication in the local newspaper of the notice in connection with which they are required to be made available, and they shall continue to be so available–
(a)where the notice is a notice of proposals, until the end of the objection period;
(b)where the notice is one announcing the holding of a hearing, until the date on which the hearing begins; and
(c)where the notice is a notice of making the designation, until the end of 6 weeks from the date on which the designation is made.