That's definitely not correct.
At some point after '87, they still made Jazz Bass Specials, just not under the Boxer series. Pickups changed from the Hot Rods to the regular small pole pieces and the bridge changed from a regular bent metal plate to a Schaller-esque bridge. Afaik, those were none export, but they do exist like that.
Oddly enough, all Boxers are Jazz Bass Specials, but not all Jazz Bass Specials are Boxers.
Here's an example of one:
Its serial starts with an H, which dates it to '88-'89.