Except for initial assessments unless otherwise specified, preauthorization by the Department or its designee is required for all services under Regulations .10 and .11 of this chapter. The Department or its designee shall issue preauthorization when the Department: Determines that services are medically necessary; and Authorizes the services before the initiation or continuance of the requested service. Authorization of services shall be rescinded by the Department or its designee when: The participant is admitted to a hospital, residential treatment center, nursing facility, or ICF/IID; The participant is no longer REM eligible; The Department determines the care is no longer medically necessary; or The participant dies.