I work at a place that sells Epi. A guy came in who using Epi and was a D2 football player. He tested positive on a random pee test and they suspended him for a short amount of time. Epi/Havoc is technically legal from my understanding but banned within sports organizations.
He was on it while taking it I believe, but nevertheless he tested hot.
The sad part is the guy didn't even know what he was taking, just that it would help him build muscle. If you're looking to compete and not have to worry about failing tests, I'd get off the ph's. Good thing that you've taken the time to ask!
I'm no biochemist or anything but I'd imagine you'll be fine within a few weeks of being off of it. Not sure if they can detect your SERM for PCT though.