Tenant paying rent late and subletting

Tenancy Deposits

Since July last year a tenant on a contractual tenancy (rent's over £500/week) has paid the rent late. I thought the house was going to be let by a professional lady in her 40's with a young child. This has not been the case. I believe she has been subletting the property to young foreign students, though I have no proof of this apart from meeting them. The official tenant is not even in the country, and the neighbours have never seen the child.

The 'subletting' students, at our last meeting, stated when I asked where they'd be moving to, that as I was evicting them, they'd get free council accomodation - I think the official tenant has misled them there, as their names aren't even on the contract.

On receiving advice from the RLA, I contacted Landlord Action and they served a section 48 (1) of the Landlord and Tenant Act 1987 at the property citing the 16th of December as the date the November payment should be made by. It was made by this date and December's rent, due on the 17th, was late again but at least it was paid.

I have contacted LandlordAction three times about whether I still have grounds for eviction based on the subletting, and also on how much time can pass since the deadline of 16th December before I proceed to the next level. Unfortunately, they haven't answered which is why I'm hoping someone at RLA could advise me.

I'm worried that my property is in danger as, when I last saw it, it looked like a bomb site and I don't know who's living there nor been able to run credit checks on them.

Many thanks

AS