In this Part “landlord” means the person for the time being entitled to receive (otherwise than as agent for another person), as between himself and the tenant, the rent paid in respect of premises comprised in a tenancy by the tenant thereof, and references to a landlord or a tenant, when used in relation to a tenancy which has terminated, shall be construed as referring to the person who was the landlord thereof or, as the case may be, the tenant thereunder, immediately before such termination.