In the pot swirl is just adding your color to the pot of soap, stir it a bit being sure to get down to the bottom, then mold. You don't fully combine the color in the pot, just mix it enough that it isn't all in one big clump.
HP and CP need the same amount of time for curing. CP is safe after full saponification, which I believe is anywhere from 12 to 24 hrs, depending on the recipe. HP is safe once it's fully cooked. Safe/fully saponified really have nothing to do with the actual cure time.
Once again,
@DeeAnna has provided the science behind the cure on her soapy stuff pages which explains why curing is important no matter if you're doing CP or HP:
https://classicbells.com/soap/cure.asp
FWIW, the reason I do HP is to prevent additives from being exposed to the lye. For that to happen, the additives have to be added after full cook, or vasaline stage.
Is there really a valid or legit reason for not allowing my additives to combine with lye? I honestly don't know the scientific answer. In my own mind, I like to think it does, but I really have no scientific evidence one way or the other.
PH just tells you how alkaline or acidic a substance is. Here is a little info on PH:
https://classicbells.com/soap/pH.asp