Another very important observation I found today:
do NOT spoof version.txt to a higher version ever, as I suggested here:
https://www.mobileread.com/forums/sh...&postcount=478
In my experiments I set it to 999,999, so any update check will report that "update" is lower than that version. However, this also murders the ability to install hotfixes!
verson.txt should be updated with new update, but this is a footgun situation nevertheless...