Where—
the original disposal was the grant of an option or right of pre-emption, and
in pursuance of the option or right, the landlord makes another disposal affecting the premises ("the later disposal") before the end of the period specified in subsection (2),
sections 11 to 17 shall have effect as if the later disposal, and not the original disposal, were the relevant disposal.
The period referred to in subsection (1)(b) is the period of four months beginning with the date by which—
notices under section 3A of the Landlord and Tenant Act 1985 (duty of new landlord to inform tenants of rights) relating to the original disposal, or
where that section does not apply, documents of any other description—
indicating that the original disposal has taken place, and
alerting the tenants to the existence of their rights under this Part and the time within which any such rights must be exercised,
have been served on the requisite majority of qualifying tenants of the constituent flats.