Yes you will. I have Diablo 3 active on my account, I have the in-game mount and I have the Annual Pass with my subscription on 1-month recurring attached to a pre-paid visa gift card which will never be charged (Mostly cause it has no money on it)
All the annual pass is is an agreement to have your subscription (1,3 or 6-month recurring) active on your account for a full 365 days. Nothing more nothing less.
How did you use the prepaid visa card with your account, did you have to use a proxy, such as paypal? or do you just enter the cards details where it asks for the expiry date etc..
Soma's guide to using pre-paid gift cards with WoW :
1) Sometimes they just fail and there is nothing you can do about it.
2) REGISTER IT ON THE WEBSITE FOR THE CARD
3) Use it just like you would any other credit card.
4) REGISTER IT ON THE WEBSITE FOR THE CARD
5) if it fails call billing and they sometimes can help with issues (For instance for some reason my billing profile once thought I had a blank extension number on my phone that was causing issues)
6) REGISTER IT ON THE WEBSITE FOR THE CARD
7) The CVV code is the three number that are italicized on the back of the card
8) REGISTER IT ON THE WEBSITE FOR THE CARD
9) Visa cards start with a 4, Mastercard cards start with a 5, American Express cards start with a 3. If it starts with any other number then it's not a credit card
10) REGISTER IT ON THE WEBSITE FOR THE CARD
I can't stress enough to register your address with the website for the card. I have never, and will never, had a credit card in my life yet I've been playing WoW for 6 years using pre-paid gift cards to buy everything from game time to my keyfob authenticator to faction, race, server transfers without many issues.
I will stress again sometimes the card will just fail and there is nothing you can do about it (Had it happen twice in 6 years where Billing could not resolve the issue - please note I'm also Canadian so using a Canadian card)
One other thing make sure the card has the amount you want to spend plus $1 for the ping charge (which falls off in a couple days) or it will fail due to insufficient funds.