Presuming you can read the user private key off the NFC chip at least once then you hold Bitcoin after the expiration of the note. No fairy tale, just math.
You need to cut the wires to do this, as I understand it. But, more relevantly, this only applies to the person who made the note. If you want to buy something with this fairly gold note, the recipient has no way to verify that it’s real unless they either trust the manufacturer or they cut the wires and transfer the Bitcoin, at which point one wonders what the point of the physical note is.
No, after expiration of the note the wire does not need to claim funds from the note. Only the user key is required.
If we as the manufacturer are perfectly untrustworthy, this is the final "backup" state. If we the manufacturer are partially trustworthy at any point in time, you can re-key the note then. In no case can we claim funds from the note ourselves.
