The plats and estimates approved by the Commission shall be kept as part of the permanent records of the Commission. Notwithstanding any other statute to the contrary: Except as permitted by the Commission, the plats prepared by the Administration are not public information or open to public inspection until they have been recorded; and Except when filed with a board of property review or a court, the estimates prepared by the Administration are not public information or open to public inspection until all the property shown on the plats has been acquired or its price determined.