Which is why Debian doesn't do upgrades-for-the-sake-of-upgrades in Stable. Anything you get there is a security fix, and the notes will tell you if there's an unavoidable functionality or config change.

It's also why you can easily set up your own repo in two stages: one that updates from upstream automatically, so you can test changes, and one that never updates except when you specifically update a package: that's the one that your production runs on.