(a) during a vacancy in the office of Chief Executive (whether or not an
appointment has previously been made to the office); or
(b) during any period when the Chief Executive is absent from duty or from
Australia, or is, for any reason, unable to perform the duties of the
office.
(a) there continues to be a vacancy in the office of Chief Executive; or
(b) the Chief Executive continues to be absent or unable to perform the
duties of the office;
then the Minister, on the recommendation of the Corporation, may appoint a person to act as the Chief Executive.
(a) the occasion for the appointment had not arisen; or
(b) there was a defect or irregularity in connection with the appointment;
or
(c) the appointment had ceased to have effect; or
(d) the occasion to act had not arisen or had ceased.