Apparently, the PineNote as delivered comes with a basic non-optimized, but fully functional Android installation, and is already capable enough if just reading is the main intended use for it.
Here is a recent video by one of the developers showing an overview of the preinstalled Android, taken before he finally replaced it with a Linux system for development:
www.youtube.com/watch?v=DWuTGgQHw98
Please note the koreader icon on the bottom left side: If koreader can be installed, any reader device becomes worthwhile.
Since the current PineNote developer edition can also be freely purchased since quite a while by more adventurous non-developers at
pine64.com/product/pinenote-developer-edition, it could turn out to be a much more future proof investment buying one of these instead of just yet another iteration of locked down consumer devices by Boyue, Boox, etc.
A pity though, that the PineNote has no SD card slot and there don't seem to be any plans including one with later hardware revisions.