What happens to the plates?
They come off, and can move to your next vehicle for $1, plus any higher registration fee
Ark. Code Ann. § 27-14-902 is explicit: on transfer the registration expires, the owner shall remove the plates, and may have them assigned to another vehicle on payment of a one dollar transfer fee, plus the difference if the new vehicle costs more to register. You can display them on the replacement vehicle before registering it, within the time the statute allows.
Source: Ark. Code Ann. § 27-14-902(a) and (b)(1)