I'm curious about this, here's my experience:
day 1- 6 months: dose A (low dose)
6 months- 1 year: dose B (double my low dose, I think "average")
1 year-1.5 yr: dose A and eventually half of dose A- I was running out of T but was on the waiting list for a new doctor because my old one was misgendering me and not testing my T levels so I didnt wanna go back for a refill
1.5 yr-2 yr: dose B again
and 2yr- now: dose C (3x dose A)
I have a relatively high voice. I really wish it changed more. It did change a lot, but it still is not a passing voice. I've always questioned whether it was the low dose and/or the instability of my dose.
My friend who is 8 months on T:
day 1- 6 months: dose B (average)
6 months-8 monhts: dose C (high)
He also has a higher voice. He obviously still has some time to change more, but he has a high voice. He too isn't happy with his changes. I believe his levels are still lowish which is why the doc keeps upping his dose. He might go up to a dose 2x what he started on.
On the contrary, two more of my friends, I think 9 months:
dose B the entire time
They have REALLY deep voices. They also might be upping to dose C.
So I have questioned often whether my voice was because of my dose, but comparing to other people I know, there really isn't much correlation. It might be because of the dose, it might not. It's not really conclusive. I don't think any big studies have been done but I'm curious about it.