5. If provisions of this Order come into operation before the day appointed by an Order in Council under section 3 of the Northern Ireland Act 1998 for the commencement of Parts II and III of that Act, then until the day so appointed—
(a)references in those provisions to an Act of the Assembly shall be read as references to a Measure of the Assembly established under section 1 of the [1973 c. 17.] Northern Ireland Assembly Act 1973; and
(b)references in those provisions to a Northern Ireland Minister shall be read as references to the head of a Northern Ireland department.