6Until sections 1 to 3 of the [1949 c. 42.] Lands Tribunal Act 1949 come into force as regards Scotland, this Schedule shall have effect as if for any reference to the Lands Tribunal for Scotland there were substituted a reference to an official arbiter appointed under Part I of the Land Compensation (Scotland) Act 1963 ; and sections 3 to 5 of that Act shall apply, subject to any necessary modifications, in relation to the determination of any question under this Schedule by an arbiter so appointed.