Dear Supkaran,
This would be considered a “substitution”. A waiver is not required to assign a substitution but the use of the replacement auditor must be logged along with the reasons for why the other auditor cannot be used for the audit. The log is maintained on SharePoint https://sharepoint.intertek.com/industrialservices/BAAuto/Lists/Auditor%20Rotation%20Waiver%20Log/AllItems.aspx
Whoever is scheduled for Surveillance # 1 audit of Watanabe has to be same for Surv # 2.