Problem Upgrading Linux Lite 3.4

[mezzmer]

There is some info on adding and removing PPA's in the Help manual - https://www.freecinema2022.gq/manual/conte...l#software

This may be useful for the desktop - https://askubuntu.com/questions/148932/h...ne-into-an

Thanks, that's helpful, you answered the next question I was going to ask - how I can see what PPAs I have installed. 

The question I was actually asking was where is it documented what PPAs I SHOULD BE USING.  i.e What are the current PPAs, and when a version goes from 3.4 to 3.6 or 3.8, how do the PPAs change?  Any insight on that?  I've had several linux installs go bad when the repos just decided to go away, and I had no idea what to do to replace them.