Sadly, if you had looked at the previously posted screenshot (identical to what I am seeing on my iPad 3), you'd notice that the "DELETE ACCOUNT LATER" selection you refer to does not exist. So, we're back to square one: how do you stop your Verizon data plan from renewing, while preserving the ability to "turn it on" later when you need it (perhaps in 3-6 months)?
This is not true today - at least not for aVerizon iPad 2 with iOS 6.1.3. I'm having a similar problem, and I just posted it. An infrequent forum visitor, I apologize for not seeing related posts beforehand.
My Verizon iPad2 USED TO have the ability to retain payment data for easy reactivation later, but it no longer does. I USED TO get a message when canceling (after a month or two) that my account would be deleted after 5 months of inactivity. I was told tonight by a Verizon rep that the only way to stop their monthly $20 charge would be for me to delete my account (which after finding no other option, I did).