It’s been that way for years, the animation in the priority editor. I agree sorting it out is a pain (as the keyframes dont’ show in the channel editor), but on the bright side, unless you go into the priority editor and set keyframes inside of it, you won’t get the behavior you are describing even with the global “auto-key” on. There is a separate auto key for just the priority editor.
Also, sometimes when the entire image jumps around on a single frame it’s because the result cam changes. That happens to me fairly often.