Howdy Diana!
We love the
PhotoPass cards that you receive at the Disney Water Parks! They are fantastic!
In the past, we have used our cards from trip to trip and never had any challenges. I would encourage you to take your card with you. Ask a PhotoPass Photographer about your card and confirm that it will still work (just in case something changes going forward). You might also check online or at one of the Camera Centers soon after you take your first few photos just to insure you don't miss any magical moments during your vacation. Hopefully, you will be able to use the card with no challenges.
As far as the 30 days, the time will reset once you begin using the PhotoPass service during your next vacation so you will have the same amount of time that you did following your last trip to view, edit and order your current photos.
I don't know if you have used
PhotoPass+ or not in the past, but I would highly recommend that you consider it for your next vacation! They do not currently have the small PhotoPass+ card that you are asking about but you can still associate your cards together so you will not have to have the PhotoPass+ card with you unless you need it to claim a photo from an attraction or dining event.
Currently, if you purchase PhotoPass+ at least 14 days prior to your vacation, the cost is $149. In my humble opinion, it's worth every penny!
Thanks so much for your question and please let me know if you need any further information. Have a magical day!