I'm not sure the best way to do this.
Lately, I've been splitting the flameout/whirlpool hops in two, and adding half at flame out and immediately chill and recirculate with immersion chiller, then once it's below 170°, I'll add the second half and continue to chill. Typically it takes a good 30 minutes or so to get below 100, and then I'll either continue to chill, or recirculate ice water through chiller, use plate chiller, CFC or whatever I'm trying out.
I have also done 20-30 minute stands without chilling and also done chill to 170 then add all the hops recirculate for twenty minutes and then resume chilling. Honestly, I'm not sure if there is a huge difference and would need to conduct experiments that I'm really not interested in doing, in order to develop a good understanding of which is the best way to go. I suspect also that hop variety will also play a role.
That said, my second year chinook hops are going bananas! Getting ready to harvest soon! Planning to use them in my next AB clone attempt.
TD
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