You can’t delete Windows 10 of the dualboot Chuwi Hi12.
There is official Windows 10 OS for the dualboot Chuwi Hi12 from Chuwi Official Forum. You had better download corresponding windows 10 system according to your tablet model. It may get a brick if you install only win10 image in your dualboot tablet.
Technically, what is the problem ? I don’t really see. Why isn’t it like a common computer ? (with a bios and rom memory)
What about the backup ? I would like to be able to backup the whole ROM in case of the tablet doesn’t work anymore since we couldn’t get back the data.
Maybe I am asking on the wrong forum. I’ll try my luck on SDA forums. (Btw, I haven’t received my tablet yet)