I had granted a AST tenancy for 6 moths to a tenant. This was for all house and only one tenant.tenant stayed at property for 9 months (3 months periodic tenancy).tenant vanished and did not inform me or returned keys. I was unable to make contact with tenant, tenants mobile diverted to answer service. I have issued a s21 notice and upon expiry will seek in courts for a possession order. now the local authority are trying to bill me the council tax from the end of 6 month tenancy, i explained to them that until possession of property has taken place, liability is still with tenant is the council right to bill me for the tax or does the liability fall once the court order is made and possession is made?