If:

(a) a maritime security plan for a maritime industry participant is in force; and
(b) the Secretary is no longer satisfied that the plan adequately addresses the relevant requirements under Division 4; and
(c) the Secretary is satisfied that it is not appropriate to direct the participant to:
(i) vary the plan under section 53; or
(ii) revise the plan under section 55;

the Secretary must, by written notice given to the participant, cancel the approval of the plan.