Don't PCT till you're done injecting test. What ether you're on will determine how long you wait to start PCT after your last pin. I asked a similar question a week ago and I was on Test E and I had to wait two weeks before starting my PCT. If you're on sustanon, its even longer.
I'm certainly no expert but I have read many times on here that Ostarine will help with joint issues while on cycle and while using Winstrol.