I can answer the 2nd part, as for a previous card just try it and see but yes they can be reprogrammed.So I had a 2020 Sonata Limited that came with the digital key card. Traded that in for the 2022 Tucson Limited, which did not come with the card. I completely forgot about it until a week after I was all traded up. So, is it possible to reprogram one of these NFC cards for another vehicle or are they only for one-time use?
Also, I'm seeing to program one of these cards requires an Android phone. I'm an iPhone user so I was curious if anyone else has temporarily borrowed an Android phone only to program/ sync the card and then continued using it without the borrowed Android phone signed in/ registered on the MyHyundai app/ website? For example, you borrowed an Android to program the card and then signed out, I'm assuming the card stays active and doesn't require an active Android associated with the MyHyundai app/ website to work moving forward?
As for Android - you need NO phone. Put the card on the charging pad. Put BOTH keyless fobs on top of the card and then follow the procedures
As an alternative, I have seen posts where people borrowed an Android phone to set it up and it worked since nothing after depends on the phone.