s 35 Duration.
(1) A designation under section 33 has effect, subject to subsections (2) to (5), during the period— (a) beginning at the time when it is made, and (b) ending with a date or at a time specified in the designation. (2) The date or time specified under subsection (1)(b) must not occur after the end of the period of 14 days beginning with the day on which the designation is made. (3) The period during which a designation has effect may be extended in writing from time to time by— (a) the person who made it, or (b) a person who could have made it (otherwise than by virtue of section 34(2)). (4) An extension shall specify the additional period during which the designation is to have effect. (5) A designation shall not have effect after the end of the period of 28 days beginning with the day on which it is made.