(1) Subject to this Act, the employment of a member of the Principal Class must be governed by a contract of employment between the member and the Secretary.
(2) The contract must be in writing and be signed by or on behalf of the Secretary and by the member.
(3) A contract of employment must specify the date on which it expires which must not be more than 5 years after the date on which it came into force.
(4) Subject to this Act, a member of the Principal Class—
(a) holds a position in the Principal Class while a contract of employment to which he or she is a party remains in force for that position; and
(b) continues to hold that position if a subsequent contract of employment is entered into for that office by him or her and the Secretary.
(5) A contract of employment may be varied at any time by a further contract between the parties.
(6) The term of the contract may not be increased beyond 5 years.
(7) A contract of employment may not vary or exclude a provision of the Public Administration Act 2004 or this Part except sections 2.4.24 to 2.4.27.