Umm I also get the feeling that the OP thinks a dbol only cycle is a good idea, which it is not.
When you start PCT depends on what you take.
Sounds to me like you are preparing your first cycle, correct? Dbol is used for a kickstart on a long-ester test cycle. If you are planning your first cycle drop the dbol - its not necessary and only adds to the complication of the cycle.
Have you factored in an on-cycle SERM or AI? I needed one when I used dbol as a jumpstart on my test cycle. If you are taking a long-estered test and you do jump start with dbol then you'll probably run more like 8-12 weeks. Which means you need hCG.
What have you planned for pct? Do you have an adequate SERM? a natty test booster? cortisol control? considered an AI post SERM to address bounceback estro?
There is alot that goes into planning a cycle. I didn't even mention support supps, on-cycle diet or training. Please make sure you address all these issues before you turn yourself into a pin cushion or pop orals till your liver becomes mush.