Tenant stopped paying rent and I refuses to answer my calls

Rent Arrears

I have a tenant in a flat rented out through an agent but I am supposed to collect the rent. The next 6 months of rent were due on the 27th of August and the tenant is not answering my calls. I have heard through the agent (who he did speak to) and my caretaker who has spoken to him that he would now rather pay the rent monthly. I am happy for him to do that but given his track record over the last 7 months of not answering my calls, I am not confident to let him pay the rent monthly. Nevertheless, I am willing to give it a try but I cannot get in touch with him. I am planning to go in to see him early next week and try and catch him but if that does not work I need to initiate legal proceedings. If he still does not pay, how long could this drag on for?

thanks for answering

Steven Zimmer