Section 6(4) of this Act shall not apply to a person who, before 10th July 1964, made a declaration in any of the forms set out in Schedule 2 to the Income Tax Act 1952, or a declaration of secrecy in a form approved by the Board.

General or Special Commissioners or other persons who made declarations in the form in Part I of Schedule 1 to the Income Tax Management Act 1964, or in the form in Schedule 2 to the Income Tax Act 1952, before the coming into force of paragraph 16 of Schedule 10 to the Finance Act 1965 (which included in the form of declaration a reference to the new taxes imposed by that Act) shall be subject to the same obligations as to secrecy with respect to those taxes as they are subject to with respect to income tax.

The repeals made by the principal Act shall not alter the effect or validity of any declaration made before the commencement of this Act.