It shall be the duty, at all times, of the trustees to act in good faith in the exercise of their powers under these regulations, and to administer the reservation in respect of which they are appointed—
(a) In such manner as will promote the purposes for which the reservation is set apart; and
(b) For the benefit of the persons for the time being entitled to the use and enjoyment of the reservation; and
(c) In accordance with the Act and these regulations, and any order of the Court in relation to the reservation.