(1) The Attorney - General may, on request by the Director - General, vary a warrant issued under this Division (other than under section 29).
(2) The variation must be in writing.
(3) If the variation extends, or further extends, the period during which the warrant is in force, the total period during which the warrant is in force must not exceed:
(a) for a warrant issued under section 25 or 26R-- 90 days; or
(b) for a warrant issued under section 25A, 26, 27, 27AA or 27C-- 6 months.
(4) The request by the Director - General must specify:
(a) the facts and other grounds on which the Director - General considers it necessary that the warrant should be varied; and
(b) where appropriate--the grounds on which the Director - General suspects a person of being engaged in or reasonably suspected by the Director - General of being engaged in, or of being likely to engage in, activities prejudicial to security.
(5) A warrant may be varied more than once under this section.