A certificate of exemption granted to a collecting society under section 10 of the Industrial Assurance Act 1923 before 13th January 1993 shall remain in force in relation to any such society as is incorporated under the 1992 Act until the certificate is revoked by the Commission notwithstanding the substitution by the 1992 Act of a new subsection for subsection (1) of section 10 of the Industrial Assurance Act 1923.