I have an number of mods loaded, but I'm not sure what might be causing the the issue.
Here's the log
https://gist.github.com/HugsLibRecordKeeper/d72e158d91d87ca08f71d79042a4bbbe
I've found the culprit by accident. I started turning off some features from the Colonist Bar KF 0.16.2.2 mod and realized my FPS started jumping.
It's definitely this mod and there are numerous comments in the thread with similar issues.