How long are Form D's in effect?

Form D's are designed to provide specific instructions or authority for a particular operation or task, and they remain in effect until fulfilled or canceled. This means that once the actions outlined in the Form D are completed, or if the Form D is otherwise canceled by an authorized person, it will no longer be valid. This helps ensure that operational protocols are clear and that the authority conveyed is time-bound to the specific task or instructions provided.

Other options, such as stating they are in effect until revoked or that they do not expire, do not accurately capture the operational nature of Form D's. While they may be in effect until specific criteria are met, such as completion of the task or cancellation, they are not intended to remain valid indefinitely or until an affirmative act of revocation occurs.