6Rebate of duty on heavy oils.
For heavy oils delivered for home use after six o'clock in the evening of 31st August 1966, the rate at which rebate of the customs or excise duty on hydrocarbon oils is allowed under section 199 of the Act of 1952 shall in all cases be a rate twopence a gallon less than the rate at which the duty in question is for the time being chargeable.