(a) The court shall disapprove the admission and order the minor discharged if it determines that the minor does not have a mental illness or an emotional disturbance of such a severity that hospitalization is necessary, or if it determines that he cannot benefit from inpatient treatment, or if it determines that a less restrictive alternative is appropriate. If any of these 3 conditions is met, the court shall order the minor discharged from hospitalization.(b) If, however, the court finds that the minor does have a mental illness or an emotional disturbance for which the minor is likely to benefit from hospitalization, but that a less restrictive alternative is appropriate, the court may order alternative treatment pursuant to Section 3-812.(c) Unless the court orders the discharge of the minor, the court shall authorize the continued hospitalization of the minor for the remainder of the admission period or may make such orders as it deems appropriate pursuant to Section 3-815. When the court has authorized continued hospitalization, no new objection to the hospitalization of the minor may be heard for 20 days without leave of the court.