Wait for January and if they have something new, it’ll be at NAMM. I seriously doubt it though. I have the impression that Yamaha doesn’t want to compete in a such a crowded market racing to the bottom (you can find a decent 61-key controller for as little as $100 nowadays, if you don’t mind the lack of aftertouch…)
The KX88 was a monster that weighted a ton and the initial version couldn’t transmit any velocity higher than 100 (the first DX7’s to hit the market had the same problem.) That was 30 years ago, of course.