What must the designating official place on the unit copy of the DD Form 285 when it is revoked?

The date of revocation is essential to document on the unit copy of the DD Form 285 when it is revoked because it establishes a clear timeline of when the authorization is no longer valid. This date ensures that all parties are aware of when the privileges were terminated, which is critical for maintaining accurate records and ensuring compliant handling of sensitive information. By having the date of revocation documented, it helps prevent any potential misunderstandings or misuse of the information that the form permits. Additionally, this practice supports accountability within the organization, allowing for proper auditing and verification processes.