24Effects of release from liability under, or loss of benefit of, covenant
(1)Any release of a person from a covenant by virtue of this Act does not affect any liability of his arising from a breach of the covenant occurring before the release.
(2)Where—
(a)by virtue of this Act a tenant is released from a tenant covenant of a tenancy, and
(b)immediately before the release another person is bound by a covenant of the tenancy imposing any liability or penalty in the event of a failure to comply with that tenant covenant,
then, as from the release of the tenant, that other person is released from the covenant mentioned in paragraph (b) to the same extent as the tenant is released from that tenant covenant.
(3)Where a person bound by a landlord or tenant covenant of a tenancy—
(a)assigns the whole or part of his interest in the premises demised by the tenancy, but
(b)is not released by virtue of this Act from the covenant (with the result that subsection (1) does not apply),
the assignment does not affect any liability of his arising from a breach of the covenant occurring before the assignment.
(4)Where by virtue of this Act a person ceases to be entitled to the benefit of a covenant, this does not affect any rights of his arising from a breach of the covenant occurring before he ceases to be so entitled.