NIS 2012 renewal with new key

I see that if you give Norton your CC info, you will be unable to delete it from your profile (and if not careful you will be billed automatically)...based on posts here. 

 

So, if I buy a renewal from the Norton Store and uncheck the box that says "Use my billing and payment information for future purchases" will my CC and billing info be saved in the Norton Account?  Or does unchecking this box just turn off auto-renewal?

 

 

I was thinking about buying a retail disc as an alternative and using that key to renew, even if that means I will lose some days on my existing key.  I know that you can click on "I have a key or code to enter" after clicking RENEW within the program, but how does the new key get associated with your existing Norton Account?