Wondering anyone knows how to get a Lattepanda Alpha R310 back to factory default / UEFI mode - my unit is stuck in a PXE boot loop.

I have a LattePanda Alpha R310 that needs to support a non-UEFI Linux image. I changed the BIOS to Legacy mode.

I am now stuck in Legacy mode, and I am unable to get back into the BIOS. Booting off a USB stick does not work, I just get the PXE Network boot screen and then an error.

I have tried the following to try and get back to defaults / UEFI mode, nothing works:

* Booting hitting ESC, DEL, all function keys, various other buttons.

* Holding down both buttons on board for 20 seconds.

* Removing battery for 1 hour.

I managed to get into the BIOS by pressing SHIFT-10 (into the Realtek BIOS), disabling the PXE BIOS, and then I could press the right key to get into the BIOS. I then disabled PXE IPV4 in the BIOS and now my system is in an endless loop of PXE booting, SHIFT-10 or any other keys no longer work.

I have emailed techsupport@lattepanda.com but no reply.

Help!