Before reading my little tangent below, just know that the most important thing you can do for PCT/recovery is start using HMG and/or HCG from day one of your cycle all the way through the end of it when the androgens have completely cleared your system.
Getting the HPTA to start signaling the testes to produce sperm/test is pretty automatic, the moment androgens dip below natural, regardless of how long you've been shutdown. The rate limiting factor is how "dead" your testes are. If you have let them be shut down for months, or worse years on end, then it can take a while, and a whole lot of blasting of HCG/HMG, for them to finally turn back on.
Best to just keep the nuts working smoothly from day one with the HCG/HMG and never let them turn off to begin with.
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It doesn't really work quite like that but lets say you were running a blast of long esters and you wanted to get as much out of the cycle as you could before coming off. Well if you just let the long esters naturally, slowly leave the body, you would have around a month or so of time where your body is low, lower, lower, lower on androgens. If you took orals or a suspension during that time you could extend the blast up through the time it takes for the long esters to clear your system, and within 1-2 days of dropping the orals/suspension you would be completely clean of androgens and your anti estrogens would be effective at boosting HPTA