5. An authorisation given under subsection 5 (4) of the Principal Act and having effect immediately before the commencement of this Act shall, on and after the date of that commencement, have effect as if given on that date under subsection 5 (4) of the Principal Act as amended by this Act, but may be revoked or varied under subsection 27 (1) of the Interpretation Act 1967.
____________________________________________________________