Adding a credit card to XBL Silver account

Hey guys, I just have a quick question here, and I was wondering if anybody actually had a solid answer.

So basically, I had the auto-renew thing goin on my XBL account. But the card I have attached to my account was recently cancelled, so I just let the gold run out and now I'm sittin here with silver. So on the My Xbox tab, I see a deal for 2 months of gold for $2 . Naturally I wanna do this, so I need to put in a new card. I'm wondering if Microsoft is going to charge my new card for another year because of the auto-renew, or if they will just let it sit so I can go and do the $2 deal. Hopefully you can understand what I'm rambling on about, and have a solid answer as well. Thanks in advance!

I think you may have to logg onto the site to cancell auto.