They haven’t scanned JP1 yet, but it’s being scanned in a very different way to much higher quality. That said Retrofilm looks like they’ve improved the quality of their scanner based on that clip which is wonderful, it’s also a real-time scanner so it scans very fast compared with how these ones are being scanned.
How much more superior is it going to look compared to the uhd?
That’s a far older transfer and only worth it for the bonus features. The 35mm will be much superior overall. 4K HDR10 or whichever soon, eventually.