I’ll tell you the answer 4k HDR.
Well it’s a good educated guess the only reason to do a new scan is really to add the HDR. You need to scan it in HDR to get the benefit of HDR.
But there would not be much point in that unless they sort out contrast color issues also anyway.
Just saying It could be good, really good. If it’s done right. It could also look totally different from what you are used to.
It needed a new scan anyway because the old lowry master isn’t even 2k, and even then it had serious issues like wrong color-timing. But the resolution of 35mm is at least 4k, so even if the lowry master looked perfect it was still only 1080p in terms of resolution, so that’s reason enough for a newer scan right there.
The HDR is added later, after the film is scanned in. Movies have been scanned and mastered in 4k for many years, since long before HDR was even invented.
Film is under 4k resolution about 3K. (areas do need to be cropped out also bear that in mind)
You can’t create color depth or a wider gammut that does not exist in a scan. either you capture it or you do not. You would need to capture it with a high exposure. It would not be any use putting your old DVD VHS or even Blu-ray and add HDR to it.
It would need to be prepared especially to have HDR and a wider color Gammut.
One estimate I read (for high quality still 35mm, mind you) is 175 megapixels. Still photography covers around 8 sprocket holes, whereas movie film is 4. A 4k 4x3 image is around 12 megapixels. I have also heard that the highest quality film stock can resolve about 6k of resolution. Honestly though, you really can’t compare the two. It’s an entirely different measurement system. No two people will give you the same estimate, and the quality of film stock varies, whereas digital is the resolution it is.