For those having trouble with the NAND b0rk/120 seconds message, although it's a bit technical I've managed to fix this issue on my box, maybe temporarily but it's working again.
Amlogic AML8726-MX HD18 v2.22 (G18ref) STB black screen no boot fix
KOPRajs, really appreciate the backporting of LibreElec. Only issue I've had is I assume my old JVC flatscreen TV doesn't like the video mode the Matricom splash uses, the display won't fire up, but I've manage to work out an order to boot the box with cables unattached until in Kodi.