If a direction under section 167 so provides, the provisions of this section shall apply in relation to a covenant or condition which—
was included in a conveyance or grant executed before the date specified in the direction, and
could not have been so included if the conveyance or grant had been executed on or after that date.
The covenant or condition shall be discharged or (if the direction so provides) modified, as from the specified date, to such extent or in such manner as may be provided by the direction; and the discharge or modification is binding on all persons entitled or capable of becoming entitled to the benefit of the covenant or condition.
The landlord by whom the conveyance or grant was executed shall, within such period as may be specified in the direction—
serve on the person registered as the proprietor of the dwelling-house, and on any person registered as the proprietor of a charge affecting the dwelling-house, a written notice informing him of the discharge or modification, and
on behalf of the person registered as the proprietor of the dwelling-house, apply to the Chief Land Registrar (and pay the appropriate fee) for notice of the discharge or modification to be entered in the register.
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