Immigration Consultants and officials working with the applications of accredited foreign representatives to Canada have been advised the following.

Diplomats, Consular Staff, or Official Personal are not allowed to apply for permanent residence for family members while such individuals are in an accredited position.

When an official working with an applicant believes that an individual applying for permanent status is related to an accredited foreign representative, they must check documents carefully as per paragraph 190(2)(a) of the Immigration and Refugee Protection Regulations (IRPR).

Once the position ends, the rules no longer apply, and the family of diplomats, consult staff, and official personal are eligible and may apply to remain in Canada as Permanent Residents. In cases of misapplication or the application of personnel you believe are ineligible, officers must inform Global Affairs Canada’s (GAC’s) Office of Protocol (XDC) and request that XDC verifies the credentials and status under the Foreign Missions and International Organization Act FMIOA. You can proceed with an application once you have confirmed the name, position and status of the foreign mission or international organization, consultants and officials and have obtained an official statement or other proof that the accreditation period has ended.

https://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/standard-requirements/foreign-representatives.html