Weighing or measuring equipment of any class prescribed under section 11 of the Act shall be treated for the purposes of the Act as if it had been duly stamped in Great Britain under that section if—
(a) it has been duly stamped in accordance with the Weights and Measures (Guernsey and Alderney) Law, 1991; or
(b) it falls to be treated for the purposes of that Law as if so stamped,
provided that this article shall not apply to a non-automatic weighing instrument to which the Non-automatic Weighing Instruments ( EEC Requirements) Regulations 1992 apply and which is first stamped on or after 1st January 2003.