(1) Subject to subsection (3) and subsection 127(1), if a person applies under section 129 for review of a decision, the Secretary, the Chief Executive Centrelink or an authorised review officer must:
(a) review the decision; and
(b) do one of the following:
(i) affirm the decision;
(ii) vary the decision;
(iii) set the decision aside and substitute a new decision.
(2) In the case of an application for review of a decision made by an officer of the Employment Department as a delegate of the Secretary, the reference in subsection (1) to an authorised review officer is to be read as a reference to an authorised review officer who is an officer of that Department.
(3) An authorised review officer may not review a decision relating to the exercise of the Secretary's power under section 181 of this Act.
(5) If:
(a) a person sets aside a decision under subsection (1); and
(b) the Secretary is satisfied that an event that did not occur would have occurred if the decision had not been made;
the Secretary may, if satisfied that it is reasonable to do so, determine that the event is taken to have occurred for the purposes of the social security law.