The repeal by this Act of subsection (3) of section 14 of the Coal Act 1938 shall not have effect so as, at any time after the coming into force of that repeal, to prevent any rights or obligations from arising in accordance with section 64 of the [1925 c. 20.] Law of Property Act 1925 (production and safe custody of documents) in respect of an acknowledgment which was deemed under that subsection to have been given to the Coal Commission.