Notwithstanding the repeal by section 1 of this Act of section 4 of the M1Road Traffic Act 1972 (in this Schedule referred to as " the principal Act") any instrument made or having effect as if made under the said section 4 shall have effect (with the appropriate adaptation of references) as if made under subsection (2) of section 96 of the principal Act as substituted by section 1 of this Act and may be varied or revoked accordingly.