The [1963 c. 2.] Betting, Gaming and Lotteries Act 1963 shall have effect as if in paragraph 3(a) of Schedule 5, after the words " six per cent " there were inserted the words " or such other percentage as may be specified in an order made by the Secretary of State by statutory instrument " and as if at the end of paragraph 3 of that Schedule there were inserted the following:—
“Any power conferred by this paragraph to make an order shall include power to vary or revoke the order by subsequent order.”