(1) This Part does not prevent the terms and conditions of a staff member's employment after the commencement day from being varied:
(a) in accordance with those terms and conditions; or
(b) by or under a law, award, determination or agreement.
(2) In this section:
"vary" , in relation to terms and conditions, includes:
(a) omitting any of those terms and conditions; and
(b) adding to those terms and conditions; and
(c) substituting new terms or conditions for any of those terms and conditions.