So, one of the reasons that I am here is to learn to read the dough. I was having trouble getting my stiff starter going. With the help of I got it started. I will post about that later. My ah ha moment was this. When my liquid starter was at peak, it looked like what I should be looking for when my bulk fermentation is complete. It was jiggly, domed, and pulling away from the sides slightly.
Here's the cool thing. I can look for these signs everyday, not just when I am baking. This never dawned on me before. 🤷
It isn't a perfect substitute, but close enough for me to practice lots.