20Exclusion or limitation of compensation in certain other cases.
(1)No compensation shall be payable under this Act in respect of any property on the ground that it has been injuriously affected by any provision contained in a scheme, if and in so far as the same provision or a provision substantially to the same effect was, at the date when the scheme came into operation, already in force by virtue of some Act, not being either this Act or an Act repealed by this Act.
(2)A person shall not be entitled to recover compensation under this Act in respect of any action taken by a responsible authority under section thirteen of this Act except in a case where a building or work which the authority have removed, pulled down or altered, was an existing building or an existing work, or a use of a building or land which they have prohibited was an existing use.
(3)Where any provision contained in a scheme could immediately before the date on which the scheme came into operation have been validly included in a scheme, order, regulation or byelaw by virtue of any other Act in force at that date, then—
(a)if no compensation would have been payable in respect of injury caused by the coming into operation of that provision in that other scheme, or that order, regulation or byelaw, no compensation shall be payable in respect of that provision of the scheme under this Act; and
(b)if compensation would have been so payable, the compensation payable in respect of that provision of the scheme under this Act shall not be greater than the compensation which would have been so payable.
(4)Where any provision of a scheme, whether made under this Act or under any Act repealed by this Act, is revoked by a subsequent scheme, no compensation shall be payable in respect of any property on the ground that it has been injuriously affected by any provision contained in the subsequent scheme if and in so far as that later provision is the same, or substantially the same, as the earlier provision so revoked; but if at the date when the revocation of that earlier provision becomes operative—
(a)there is still outstanding any claim for compensation duly made thereunder; or
(b)the time originally limited for making such a claim has not expired,
any such outstanding claim and any such claim made within the time so limited shall be entertained and determined, and may be enforced, in the same manner in all respects as if all the provisions of the earlier scheme had continued in operation.