(1) The provisions of this Part shall apply subject to so much of any Act which contains provisions relating to or affecting excise duties as -

(a) is not repealed by this Part, and

(b) would have operated in relation to these duties if this Part had not been substituted for the repealed enactments.

(2) The continuity of the operation of the law relating to excise duties shall not be affected by the substitution of this Part for the repealed enactments.

(3) Any reference, whether express or implied, in any enactment or document (including this Part) -

(a) to any provision of this Part, or

(b) to things done or to be done under or for the purposes of any provision of this Part,

shall, if and in so far as the nature of the reference permits, be construed as including, in relation to the times, years or periods, circumstances or purposes in relation to which the corresponding provision in the repealed enactments applied or had applied, a reference to, or, as the case may be, to things done or to be done under or for the purposes of, that corresponding provision.

(4) Any reference, whether express or implied, in any enactment or document (including the repealed enactments and enactments passed and documents made) -

(a) to any provision of the repealed enactments, or