64.—(1) An appeal shall not lie under regulation 63 against anything done by the Board in the exercise of a power conferred by these Regulations which is expressly declared by these Regulations to be a power which they are to exercise in their discretion.
(2) Subject to regulation 69(2), in any proceedings under regulation 63 the court or tribunal shall be bound by any final decision of a medical authority within the meaning of regulation 69(4).