Originally Posted by JesseL
Is growth complete when activity is no longer visible?
I can't speak to what a starter not
spun on a plate looks like, but I can tell you that if you are using a plate the yeast will visually indicate when it's completed it's growth phase.
From experience every strain I have ever used will floc into clumps (if it is a flocculent strain) or at the very least stratify in the flask even while the plate is still running. If the color of the contents of the flask is completely uniform and opaque with no visible clumping or stratification, it isn't done. I've never had it take more than 36 hours at 70f to show these signs of completion. YMMV of course, but from what I've seen even very low flocculating (I refer to them as "dusty") yeasts will stratify and begin to visually swirl in the flask when growth is complete.