To many variables for someone to decide for you. Most (as above) preach time on = time off. That is not set in stone of course. That is for the general lad who wants to be safe, healthy and fertile.
Examine your current health, goals in BB, AGE, risks you are willing to wager, and how fertile you are worried about staying.
Some younger guys seem to be more worried about nat test production and fertility rather than things like lipids and heart health.
Do your research and then decide. Some of the PCT medications seems as they can be more harsh on the body than the AAS.
Good luck