Where—
as a result of one or more assignments a person is the tenant of part only of the premises demised by a tenancy, and
under a proviso or stipulation in the tenancy there is a right of re-entry or forfeiture for a breach of a tenant covenant of the tenancy, and
the right is (apart from this subsection) exercisable in relation to that part and other land demised by the tenancy,
the right shall nevertheless, in connection with a breach of any such covenant by that person, be taken to be a right exercisable only in relation to that part.
Where—
a company which is being wound up, or a trustee in bankruptcy, is as a result of one or more assignments the tenant of part only of the premises demised by a tenancy, and
the liquidator of the company exercises his power under section 178 of the Insolvency Act 1986, or the trustee in bankruptcy exercises his power under section 315 of that Act, to disclaim property demised by the tenancy,
the power is exercisable only in relation to the part of the premises referred to in paragraph (a).