Where on the coming to an end of a tenancy at a low rent the person who was tenant thereunder immediately before the coming to an end thereof becomes (whether by grant or by implication of law) tenant of the whole or any part of the property comprised therein under another tenancy at a low rent, then if the first tenancy was a long tenancy or is deemed by virtue of this subsection to have been a long tenancy . . . the second tenancy shall be deemed for the purposes of this Part of this Act to be a long tenancy irrespective of its terms.
In relation to a tenancy from year to year or other tenancy not granted for a term of years certain, being a tenancy which by virtue of the last foregoing subsection is to be deemed to be a long tenancy, this Part of this Act shall have effect subject to the modifications set out in the Fourth Schedule to this Act.