TrainingPeaks (TP) can offer better information the longer and more consistently you use it.
The below link references 42 days:
If you’re just starting with TP, I would keep tracking your workouts without changes and then you can see what TP tells you.
Alternatively, if you need/want to make changes to your workout, then listen to your body and reflect on how you feel/how you recover after the changes. Ex. You increase volume/intensity and discover you need 3 days to recover…that will indicate the increase was likely too aggressive