Reading back on it, Y-10 was really an outdated design and it was quite expensive project at that time for PRC, so it was cancelled. Also, the quality of the plane was not good enough for the Chinese airline. As for Y8F600 and Y-9, I honestly can't see much difference. Maybe better airframe and avionics for Y-9? It's probably an interim frame before Y-8X. I'd honestly like to see China just abandon these updates to Y-8 series and start cooperating with Antonov on An-70.