42 CFR §8.21

1. (a)The Secretary has notified an OTP in writing that its certification under the regulations in subpart B of this part has been suspended or that the Secretary proposes to revoke the certification; and
2. (b)The OTP has, within 30 days of the date of the notification or within 3 days of the date of the notification when seeking an expedited review of a suspension, requested in writing to the reviewing official, an opportunity for an informal review of the suspension or proposed revocation.
3. (c)The Secretary has notified an Accreditation Body of an adverse action taken regarding withdrawal of approval of the Accreditation Body under the regulations in subpart A of this part; and
4. (d)The Accreditation Body has, within 30 days of the date of the notification, requested in writing an opportunity for a review of the adverse action.