18When new duties of Customs are imposed former ones to continue until the new become chargeable, except in certain cases. Duties due before the passing of this Act to be levied as if payable by this Act.
In all cases where any new duties of Customs or other duties, rates, or charges under the management, collection, or control of the Commissioners of Customs are or may be imposed by any Act of Parliament, or by any resolution of the house of Commons, in lieu of any duties payable at the time of the passing of such Act, such former duties shall be and continue payable until such new duties imposed in lieu thereof shall become chargeable, save and except in cases where the Act or resolution imposing such new duties shall otherwise provide; and all moneys arising from any duties of Customs, rates, or charges, or any arrears thereof, payable on account of any goods whatever imported into or exported from the United Kingdom under any former Act, although computed under such former Act, and whether secured by bond or otherwise, shall be levied, paid, and appropriated in the same manner as if the same had been made payable by this or any other Act in force for the time being; and all drawbacks or allowances payable under any former Act shall be paid or allowed under this or such other Act as may be in force for the time being.