Just re-starting out (less than a week now) and I am feeling great, not able to sleep without waking a few times, but honestly don't care, I feel better and the mask works for me!
That said, I am diagnosed positional, with right side at <5 AHI, but supine of 35 AHI from several years ago (waiting my home study results from last night for changes).
I am seeing significant difference when I try to sleep on my back (which I want to be able to do sometimes!).
Here is a typical evening results, with overall AHI of ~2, but with the second session only I tried on my back twice, with over ~6AHI. Even then, I know I turned to my side to between.
Given I am currently prescribed the broad range of 6 to 16, too me I should be more like 8 to 16, but I feel like my back sleeping never gets to max because I change positions before pressure autoset's back down. Anyone have advice?

Start and middle on back, remaining on side:

-----
ResMed AirSense 11 AutoSet
6 to 16, ERP fulltime 1
ResMed AirFit F20 full face mask