With the Fairphone you get more than just a replaceable battery. You get replaceable nearly everything. Also they do their best to ethically source the materials. In terms of ROMs there is also Iodé, also based on LOS, and if you go with a FP4 instead Ubuntu Touch.
Accidentally flashed a live image (PCBSD, IIRC) onto my 1TB external HDD instead of the thumb drive. Lost years of collected music and movies that night. I learned two things:
Don’t do this sort of thing in the middle of the night, when you’re tired and should be sleeping.
You can either try to contact the seller and ask for the password or just erase the UEFI settings by shorting some jumper or something. There should be instructions how to do that for your specific model.