A bit of theory here.
Without agitation the developing agents in the film and just outside the film (about 0.1mm, IIRC) becomes used up. That 0.1mm acts as a barrier keeping fresh developing agents from entering the emulsion. So development stops at that point. Past that point very little goes on, you can actually leave the film setting there for several hours with very little increase in density.
Now with increased temperatures, within limits, what happens is the developing agents are used up faster, so developing ends sooner. Those limits, IIRC, are from 60F to 85F. At higher temps Brownian motion starts providing self-agitation.
I have let film set for over two hours with no noticeable increase in density, I have not tried to see how soon I could pull it, but I would guess at a point only slightly longer than it takes to process the film by time and temperature with normal agitation at that dilution.
As I have said, I have been using this method for a couple of years, and except for the last two batches (of of one roll of 120, and the other of two rolls of 120), all those negatives are about the same density. All at room temperature with no adjustment for seasonal changes. So, I concluded that something has changed without my being aware of it, and came here where I felt the experts were for help. What I get is told that two years of experience is wrong.
Now, I have read a lot about stand developing on the web, and in almost every case I noticed that the person trying it could not believe it did not need additional agitation, so did not actually use stand developing. The few that did not do additional agitation reported the same results I have had. Once you get into having to do temperature control outside of broad limits, stand development loses all of its advantages, and you might as well go back to time and temperature. Which all those saying I do not know what I am talking about, seem to have done.
For those who have to know the details: I mix Rodinol 600ml + 6ml. 600ml water stop. 540ml + 60ml fix. All dumped after one use. I then do a modified Ilford wash. To insure consistency I agitate each with 5 slow inversions, then set until the time is up. The only thing that is at all critical in this system is agitation, which is why I chose to use the same agitation for all cycles. If I do it the same for everything, I will not forget and do it wrong for the critical developer stage (I have a neurological problem, that I translate what the doctors are saying as, "Duh, I do'no", complicated by a-fib & a nasty form of sleep apnea, which makes life interesting. Read interesting as meaning it make it very hard to get up and get started at anything. Strangely, once started you only seem to have a sight handicap, in that you run out of steam in a couple of hours, and are somewhat absent minded.)
For anyone reading this thread, wondering about stand development, don't take anyone's word for it, try it yourself. The simple fact is that we can all be right, slight changes in the system can account for the differences mentioned here.