(1)  The parties to a registered enterprise agreement, by mutual consent, may make a further agreement to vary the registered enterprise agreement.

(2)  If the parties to the registered enterprise agreement (other than the enterprise employer) include individuals or an employee committee, a further agreement to vary may be entered into by those individuals or that employee committee only after at least 60% of the persons employed in the enterprise in the one or more classes of employment to which the enterprise agreement applies agree to it by secret ballot.

(3)  A further agreement to vary a registered enterprise agreement remains in force for the remainder of the period during which the registered enterprise agreement remains in force.

(4)  On the registration of a further agreement under this Part, a registered enterprise agreement as varied by that further agreement has effect as so varied.