Scenario in short:
I’m trying to install LineageOS onto a spare phone that I have (redmi note 8T) Hoping to get a daily driver out of it. The installation process requires me to install Android11 to install lineage on top of /over that. Which afaik isn’t directly available outside of some websites that I’ve never heard of.
For safety’s sake: would the install of lineage wipe the install of Android11? Or could there still remain backdoors?


Good to know. I also see you already found the official Lineage OS installation guide. Whatever upgrade/downgrade the LOS devs say needs to be done should be safe as long as you don’t deviate from the instructions.