As mentioned: Ask knc1 for the password.
Can confirm the same procedure as sigismond1 (PW3, running 5.8.10.0.1 out of the box), except I've used the 5.8.9.0.1 factory test build for downgrading. No bootloops or any other Problems!
Gesendet von meinem Google Pixel mit Yabba-Dabba-Talk.