First stack in non-steroidal, so you won't need any normalization period, or "down-time" as you put it. However, you will after S-Roid...I will tell you that.
I'm going to disagree just a bit here, so please forgive me...
Take a break. Stop using any/all "hormonal" products for the same amount of time you were on them. If on MFX/HX2 for 4 weeks, take 4 off. Though they don't cause any shutdown, they still modify hormone levels - thusly why I still refer to them as "hormonal" products. Taking that break will enable your body to recover from the 'tampering' that you just did. Always keep in mind that the body wants to be in stasis - a point where everything is level, happy, hunky dory, and content. Upsetting the balance causes the body to change and react. In the case of weight training, to grow bigger/stronger/leaner/etc. In the case of supplementing, to readjust levels to combat outside influences through modified hormone levels. Not to mention that you'll also have fresher receptors should you take that break, too. It's just a good idea. Being burnt out from overuse is easy to do, and not adviseable ever.
Also, I'm hoping that you do realize the potency of S-roid, the dangerous side effects of the compound, and what proper PCT will entail. If you're not sure, search the steroid forum for Mdrol, or Superdrol. Read up a LOT on it. Then read more. Then sit and digest for a few weeks while you take that break I mentioned. Then come back, read more, save some pennies, and do it right. Just because it's out there doesn't mean you need to take it.