The commissioner shall, upon proper application for admission, forthwith admit the eligible person with a developmental disability, and provide him with appropriate functional service to the extent available. In the event that the functional service which has been specified as most appropriate from time to time is not immediately available, the commissioner shall provide alternate service and, at the request of the applicant, shall also place the eligible person on a waiting list for the preferred service pending its availability.
N.J.S. § 30:4-25.6