@mario-ch

I actually downloaded 4 versions of the OEM after I read the post, and numbered them. Then went through the whole spiel with fastboot, wipe, twrp, oem, ubports.

it worked with
TWRP 36090 kugo
OEM SW AOSP v08 loire
UBports 0.8.9.
and some patience.
Finalizing install now, thanks a lot!