There's some speculation that it's the same chip as the one in the Pimax 4K, but I haven't be able to locate a specific chip model for the M1. So far, the details have been vague. The reason I think it's a very simple chip is that there was some discussion that it only supported 1440p upconversion to 3840x2160p and had no 1080p upscale support.
Here are components* of 8K V1-V2:
1x DP 1.4 to 2xHDMI splitter, unknown maker(performs almost no logic).
2x HDMI to DisplayPort Bridge Controller ANX7678, in specs noted it is designed for use with ANX7530. Specs3.
2x ANX7530 . Used to accept out from anx7678(2160v x3840h (DSC 2:1)) and sent to MIPI, actual DSC(real deal, used Algorithm not just math to reduce BW) to each MIPI 1080v x 1920h, 2MIPI per eye, so we get not uspcaled, but decompressed 4K per eye output res. Not native, but decoded/decompressed/restored res. Much better than dumb upscaling.
Why this method won't work with 1xDP and direct DP to anx7530, because anx7530 is not designed for native DSC 1.4, but to be fed via anx7678, then the claim DP 1.4 compatible have sense. This guys design HW they are correct always or HW is junk.
Here's a link to the discussion threads...