You're right that it's important to observe the dough and modify timing as needed. I think, however, that for many folks who are trying out baking sourdough fo

You're right that it's important to observe the dough and modify timing as needed. I think, however, that for many folks who are trying out baking sourdough for the first time, it helps them a lot to start with a fully detailed recipe that includes timing. The instructions on that bread scheduler will AT LEAST get you to the right ball park (assuming you use similar flour to the instructions). For those starting this out, I would recommend following one of these detailed recipes, do it several times or more, and that way develop some sense of what factors to tweak. Taking a closer look at the instructions, I see they're not emphasizing dough temperature during bulk ferment. Household kitchen temperatures can vary quite widely and this temperature is an important factor in how long the dough takes to ferment. That's why it's valuable to press the dough with your finger and gauge readiness prior to shaping steps.