The landlord is a housing association or housing trust which lets dwelling-houses only for occupation (whether alone or with others) by persons whose circumstances (other than merely financial circumstances) make it especially difficult for them to satisfy their need for housing, and—
(a)either there is no longer such a person residing in the dwelling-house or the tenant has received from a local housing authority an offer of accommodation in premises which are to be let as a separate dwelling under a secure tenancy, and
(b)the landlord requires the dwelling-house for occupation (whether alone or with members of his family) by such a person.