It's late here, but I'll try to provide the serial console logs tomorrow.
What I did was quite straight forward. Downloaded the Image, flashed it to a SD card with etcher, booted, logged in as root via ssh, created new user, changed IP to a static IP, rebooted, logged in as new user, tried to update, reboot - no more lights, no longer able to connect. Tried this with armbian-config, with apt update and with the bionic Image. Always the same result.