Thank you for giving me the opportunity to clarify. I believe it is section 18, not section 48. Section 18 of the Citizenship Act provides a good procedure for this.
Section 18 states that the minister needs to notify the applicant whose citizenship is in question prior to its being revoked. The applicant also sees that I said a certificate of renunciation would be issued after the process is completed. Of course, an individual could seek leave to appeal to the Federal Court as well.