A petition for the appointment of a guardian, conservator or both of a minor may be filed if the minor is at least seventeen years and ten months of age and the petition alleges that the minor would qualify as a "protected person", as that term is defined in section four, article one of this chapter, if he or she were an adult. The hearing provided for in section nine of this article shall occur no sooner than fourteen days prior to the alleged protected person's eighteenth birthday if the trier of fact is the mental hygiene commissioner and no more than seven days prior to said date if the circuit judge conducts the hearing.