Will this hold any legal weight?

I cancelled my account with DTV and was assessed an early termination fee. When I cancelled the gal said, “All final bills and charges will be charged against the financial information we have for you.”
I said, “I figured you’d do that so I cancelled my card today. I will pay my bill, and then $10 or $20 a month on the early termination fee. I understand it may go to collections, and that’s fine. I’ll just pay them $10 or $20 a month until it’s paid off.”
I heard a kind of “Ooof!” at the other end. :D

Well, today I made my first payment. Before I gave them the number, I made sure it was being recorded, got the rep’s name, made a note of the date and exact time and said, “This financial information may only be used at my direction. You can not take out more than what I authorize.”

So…do you think that will cover me, or are they probably going to debit it anyway?