Tenant needs to get proper legal advice but see below
Section 16 ofLandlord and Tenant Act 1980 provides that a tenant will be entitled to a new tenancy at the expiry of his existing lease if he can prove one of the following equities
Business equity-if the tenant was in occupation for 5 years continuously and was using the premises/tenement for business purposes (this period used to be 3 years); temporary breaks can be disregarded by the courts. The five year period only applies to tenancies/leases which commence after 10 August 1994 and the tenant must occupy the tenement for the entire period