Between 2014 and 2018 an estimated 30,000 flexible tenancies were granted by local authorities. If a flexible tenancy has been granted to you, your landlord may well be frustrated in any attempt to get you out before the fixed term of the tenancy has come to an end. A judgment of the Court of Appeal in a case called Croydon London Borough Council v Kalongola  EWCA Civ 77 has made it clear that without a so-called forfeiture clause in your tenancy agreement - you should check with a professional on whether you've got one - the landlord cannot bring the tenancy to an early end. And, even if there is a forfeiture clause in the agreement, there are certain technical steps the landlord would need to take before it could secure a court order for possession against you.
Croydon has been refused permission to appeal to the Supreme Court. It might seek permission from the Supreme Courts itself. We shall see.