I have been using a letting agency to represent one of my properties for a few years. I was not happy with their service so I told them I wished to terminate my contract. On the day the contract ended (29th Feb) I was told I needed to pay a termination fee of one month's rent.

I had called their office the previous month to clarify whether this fee was one month's rental fee or one months rent and was told it was just the rental fee. However, the boss of the company has been in touch and pointed out where it says this on the contract and that I would need to pay one full month's rent or go to court. I agreed that I would pay and set up a standing order for the 31st of this month. I have now received an email saying that this date is too late and they will instruct solicitors to file papers on Monday saying that I was in breach of contract. They said this will be presented to court on the 23rd (7 days before I am intending to pay anyway).

I have tried to be reasonable and given them a date (within a month after the contract ended), but I don't have the money to pay at the moment. Maybe they just want to scare me to get the money, but do they have a case? Further more, can I argue that they have already broken the contract because from July last year to January I found out that they were taking £50 per month more from my tenant than their statements showed (short changing me by £50 per month). When pointed out to them they refunded the missing money in the next statement, but how does this change the situation? Are there some magic words I can say that will stop them being nasty and will let them wait until the 31st of March?

Optional Information:
Province/Country relating to question : England

Already Tried:
I have tried being nice and agreeing a payment date within one calendar month. I have asked for a phone number so I can speak to the boss directly, but that email was not responded to. They have tried a series of threatening emails.