As mentioned a few days ago, Tom's released three new videos on sourdough bulk fermentation that I highly recommend. Since they total about 3 hours of viewing time, I used by AI friend, NotebookLM, to create a summary presentation on bulk fermentation diagnostics.
Reviewing the presentation alone won't fix all your bulk fermentation challenges, but it provides a pretty decent overview to help you understand the process and better determine underproofing, overproofing, and ideal fermentation.