Have a property let to 2 joint tenants who took the house on as a couple but are now splitting up. One of the tenants wishes to keep the house on. Initial 6 month period expired last year and tenancy has rolled on on a month-by-month basis. Am I now best to start a new 6 month STA with the remaining tenant, despite this dropping me into the TDS pit? And do I have to put anything in writing to the leaving tenant?