Hi there. I realize this is an old thread, its now July 2022.
I just updated one of my (ODYSSEY-X86J4105 without eMMC) and followed the instructions (multiple times, doing EC upgrade first). Silly me, I should have left it alone.
Now I have the same issue on the unit - wont boot. It ends on black screen with Curser on top left corner. I purchased from Amazon in Canada - Sold by / Vendu par SEEED DEVELOPMENT LIMITED in 2021
Just wondering if there are ideas on a possible fix yet? I love these units!
Rob