I don’t do upgrades (well, not in the sense most people think of them).

My approach is that upgrades are too risky, things always break. It’s also why I don’t permit auto updates on anything. I’d rather do manual updates than dedicated time. Keeping things working is more important, and I have backups.

I run everything virtualized (as much as I can), so I can test upgrades by cloning a system and upgrading the clone. If that fails, I simply build a new system based on some templates I keep. Run in parallel, copy config and data as best I can, then migrate.

This is a common methodology in enterprise, which virtualization makes a lot easier for us self hosters.

I haven’t had a disruption from updates/upgrades in 5 years.