(1) At any time after the issue of a certificate under section 99 the Chief Labour Officer may, after consultation with the trade union named in the certificate and the appropriate employers’ organization, issue an amending certificate varying the class of workers specified in the certificate and any reference in this Act to a certificate issued under section 99 shall be deemed to include such a certificate as amended under this section.

(2) The issuance of an amending certificate shall not affect the membership of a standing negotiating committee or a joint standing negotiating committee appointed under section 101, but the employer or workers of the class specified in the certificate as varied by the amending certificate, may nominate representatives to act either in the place of or together with their existing representatives.

(3) When an amending certificate is issued, the chief Labour Officer shall cause a copy of the amending certificate to be published in the Gazette.

(4) When an amending certificate is issued, extending the class of workers specified in the original certificate, and there is in force a collective agreement which applies to all workers of the class specified in the original certificate, the trade union named in the certificate shall take such steps as appear to it to be appropriate for bringing that agreement to the attention of all the workers to whom the agreement is extended by the amending certificate.

(5) When an amending certificate is issued excluding any persons from the class of workers specified in the original certificate, and there is in force a collective agreement which applied to those persons, the amending certificate shall not affect that application of the agreement to them, or any right to vary it, but a collective agreement made after the issue of the amending certificate by another trade union shall have effect notwithstanding anything in the previous agreement.