9Where at the operative date (within the meaning of paragraph 5 above) land consisting of or including a dwelling-house is subject to a long tenancy which becomes a regulated tenancy on the operative date by virtue of section 39 of this Act, then section 42 of the [1965 c. 75.] Rent Act 1965 (which makes provision for relieving mortgagors from hardship in connection with mortgages created before the commencement of that Act) shall have effect as if in relation to that land the reference in subsection (1)(a) to the commencement of that Act were a reference to the operative date.