JJ is not giving any starting piety. Ever. I just tested it about 20 times and it was "rolling imaginary dice" "0 piety" every single time. That includes prepped versus purist and everywhere from 0% map revealed to 100% map revealed.
(This better be a bug, and not deliberate... I'm guessing the reason no one has reported this yet is that no one is even using JJ as a starter deity anymore anyway (
), since he takes way too long to start being beneficial, and isn't even stronger in the long run than deities who have quicker starts.)