The director may be nominated by any one of the following to act as guardian or conservator for any developmentally disabled person; (1) who is or may become eligible for the services of a regional center, or (2) who is a patient in any state hospital, and who was admitted or committed to such hospital from a county served by a regional center:

1. (a) A parent, relative or friend.
2. (b) The guardian or conservator of the person or estate, or person and estate, of the developmentally disabled person to act as his successor.

3. (c) The developmentally disabled person.

   Such nomination shall be in writing and may provide that the authority of the director is to take effect at some date or occurrence in the future that may be fixed in the nomination.

   The director shall promptly accept or reject such nomination in writing. His acceptance shall be binding upon him and his successors. Any nomination to take effect in the future may be withdrawn by the nominator before its effective date.