I mean, I'm not super-concerned with the prospect of wasting $15... it's the principle of the thing.
He'll get a new expiry date. Credit card companies don't issue you a new number unless they really have to (card was use fraudulently)
Instead they just issue you a new expiry and CVC - and often even update merchants who are charging you on a regular basis with the new info, or allow transactions to continue to go through even with expired date/cvc
Still a valid concern regarding the card # being replaced due to fraud. I keep an encrypted list of all my past CC #s for this very purpose: Far too many places use the CC# as a life-long immutable number (think SSN).
What I was wondering is if he had to re-validate at some point in the future, would the expired card trip him up or would his encrypted copy still work?
I'd guess it would still work if he is doing this all without a network connection. If that works though, I hope their using the credit card info as a hash instead of directly storing it in their encrypted files... because that would be scary.
Last week I finally broke down and bought a DRM book from B&N's website. It let me download an encrypted EPUB file, which I transferred to my Nook over USB. Without having to enable WiFi or register my Nook, I was able to open and read the EPUB just by entering my name and the credit card number used to purchase the book. (By the way, I only had to do this once.)
It still sucks because it's DRM, but I'm reasonably confident that with this setup, B&N can't remotely kill my books, and it should keep working even if B&N goes bust. You might want to consider it.