69Documentary evidence as to sums due for services
(1)A certificate of the Post Office that a specified sum is due to it from a specified person under provisions of a scheme made under section 28 of this Act with respect to telecommunication services shall, in any proceedings instituted by it against him or his personal representatives or against it by him or his personal representatives, be evidence (and, in Scotland, sufficient evidence) of that fact.
(2)A certificate of the Post Office that a specified sum is due to it from a specified person under an agreement with respect to telecommunication services provided by it shall (subject to any term of the agreement to the contrary), in any proceedings instituted by it against him or his personal representatives or against it by him or his personal representatives, be evidence (and, in Scotland, sufficient evidence) of that fact.
(3)In any proceedings instituted by or against the Post Office to which the rate at which a charge was levied at any time, in respect of a service, by an authority outside the British Islands is material, a certificate of the Post Office that the charge was levied at that rate at that time in respect of that service by that authority shall be conclusive evidence of that fact.