First Post, Bipap auto setting question.

Hi everyone!. First post. Pardon rookie errors please!
Have had cpap for 11 years. Last titration, 11 years ago, (yeah, I know...)
So, I did another sleep study finally because of brain fog problems last two years.
they tested me at 9 cms, and during sleep study, they tested that and I was having AHI of 73....brain fog is probably now explained by me not knowing how off the 9 cm titration was.

fast forward, I've been titrated at 11 inhale, 9 exhale, by a board certified sleep dr/pulmonologist I trust. He seems like a good one!

my question is, when I get this bipap, it will be locked at 11/9, and I'm going to keep it at that. My insurance will be lower quality so I was wondering if after one or two months following my doctor's guidelines of 11/9, if I decided to unlock it and take it to auto mode, what are the best "ranges" to set it at. I don't understand after lots of research how that would work. I don't want 4 to 20 because I read somewhere that it takes longer for the machine to figure out where you should be at. So what's the typical medically approved way of setting an auto if your sleep study said 11/9. Like I said though, I'm going to use the strict 11/9 for 8 weeks or so, but if I'm having too many ahi's because of a beer I drank or I get fatter, or thinner, just wonder how to range out the auto....
Thank you in advance for any help and advice, and thanks for understanding any knowledge errors I may have made in this question.

this should answer many of your questions.I see I missed the link ... now I don't rember what it was
I found the link I wanted to insert:

viewtopic/t102376/Bipap-settings-are-mysterious.html

Spartacus -- Welcome to the forum. Best thing to do is monitor your therapy with software like SleepyHead and then evaluate after those first couple of months whether your pressures even need to be adjusted. They may not need to be changed at all. If you're uncertain you could post some screenshots of your SleepyHead reports and get feedback when the time comes.

Welcome to the forum.
In terms of what settings might do what you are wanting to do...it depends on how well the current settings are working for you.
11/9 is a tiny fixed bilevel pressure support. Odd that they want those settings but oh well...
We can help with ideas for auto mode pressures but we need to know what 11/9 is doing first...and how well you are handling 11/9...and do you want to keep the 2 cm pressure support (PS is just the difference between inhale and exhale).
All of this can be determined later once you get your machine and spend some time at the current RX settings.

Thanks guys, I got my machine tonight! Fingers crossed!
Thanks again!