What is the law during the time of Melchizedek?

Hebrews 7:12 provides: >“For when the priesthood is changed, the law must be changed also.” ‭ In Hebrews 7:11, the change in priesthood refers to a change from the order of Aaron to the order of Melchizedek. Accordingly, the change in law refers to a change from the law given during the priesthood of Aaron and back into the law given during the priesthood of Melchizedek.