I'm not sure about the ultimate edition, but I got 24 packs by pre-ordering at gamestop. I would check the online app when you know the packs will drop. With the EA sports season ticket the packs will expire a week after they've been given out (available for you to open). So while it's not a direct answer I would not take my chances by letting them possibly expire.
You can open your packs on the fifa13 Ultimate team web app. Once you log in, go to the store tab at the top of the screen. I've noticed when I have a pack available that tab will have a red border with the number 1 in it. (for 1 item available). Once there go to "My packs" and go ahead and open it. You can store to your club or ago ahead and put them in the line up. Either way they will be available for you when you connect to EAs servers again on your console.