Have you reached your natural genetic potential yet?
I have read that if you are someone who has (for example) only put on 5 pounds of muscle before starting AAS and then go on a cycle, and put on (say 10 pounds of solid muscle- not including water retention) that because your body, at normal Test Levels can support this level of muscularity, you will (if smart) keep most of those gains (because you have not reached anywhere close to the natural limit of muscle your particular body can handle).
Of course if you've only put on 5 pounds of muscle before going on gear you aren't doing everything correctly and probably shouldn't be using AAS in the first place! I have read you will fuck up your ligaments because your strength will grown faster than your bodies ability to adapt to the pressure
Old Pug