Ashwagandha, in addition to having a cool name, is high on my list of things to test and here you have not only been testing it for seven years but you have been doing it correctly and not mixing a lot of other variables!
So, how have your PD and meds changed?
With all those centuries of use without a reputation for toxicity and with a reputation as a first-line adaptogen, and now it is found to promote regrowth...