This section applies in any case where a farm business tenancy (“the new tenancy”) arises between—
a person who immediately before the date of the beginning of the tenancy was entitled to a severed part of the reversionary estate in the land comprised in a farm business tenancy (“the original tenancy”) in which the land to which the new tenancy relates was then comprised, and
the person who immediately before that date was the tenant under the original tenancy,
and the rent payable under the new tenancy at its beginning represents merely the appropriate portion of the rent payable under the original tenancy immediately before the beginning of the new tenancy.
In any case where this section applies—
references to the beginning of the tenancy in subsection (6) of section 10 of this Act shall be taken to be references to the beginning of the original tenancy, and
references to rent in that subsection shall be taken to be references to the rent payable under the original tenancy,
until the first occasion following the beginning of the new tenancy on which any such direction, determination or agreement with respect to the rent of the new holding as is mentioned in that subsection takes effect.