As from the appointed day, paragraph 45(e) of Schedule 4 to the [1967 c. 1.] Land Commission Act 1967 shall have effect as if the reference to expenditure which has been or is to be met directly or indirectly by a government department did not include expenditure incurred by the Postmaster General in relation to land in the case of which an interest therein vests in the Post Office by virtue of section 16 of this Act.