4.—(1) Where a pension authority has power by virtue of the preceding Article to increase any pension specified in Part II of Schedule 2 to the Act of 1971 (which relates to pensions payable by local authorities etc.) it shall be the duty of the authority to exercise the power.
(2) Section 7(2) and (3) of the Act of 1971 and Article 9(3) of the Superannuation (Northern Ireland) Order 1972 [1972 NI 10] (which among other things relate to the manner in which certain increases under the Act of 1971 are to be paid or borne and in which the cost of them is to be apportioned) shall have effect as if references to the Act of 1971 included references to this Order.
(3) Regulations may provide that, in relation to any pensions specified in the regulations, functions of the pension authority under this Order shall be performed on behalf of the pension authority by such other authority as is so specified.
(4) In calculating the rate of any derivative pension any increase under this Order of the principal pension shall be disregarded.