AHI over 20 at 6000ft altitude?

I was diagnosed with mild OSA (AHI 10.6 in sleep test) in 2015, and have been using a CPAP sporadically since with limited success. Most nights my AHI is in the 2-5 range, though I still don't feel particularly more rested.

I'm spending this month at an altitude of 6200ft, which has been going quite poorly for my sleep. After a few nights without a CPAP, I just got a new Dreamstation Go and was surprised to see my AHI through the roof for a few days with readings of 11.04, 10.30, and 22.34.

I raised my maximum pressure from 13cm to 16cm before that last night, which seems to only have made things worse. I remember waking up quite frequently and being annoyed by my mask going at full blast, though which of those is cause or effect is unclear. The night was going so poorly that I ended up lowering to 14cm around 4am, and down to a pitiful 9cm at 7am in hopes of salvaging at least some sleep.

Clearly something is going quite wrong here, though I can't tell what. Should I raise the pressure higher than 16cm since I was reaching that upper threshold? Lower the pressure since it doesn't seem to be helping and possibly making things worse? Suffer through a full night at 16cm? Anything else?

I am wondering if the centrals are causing arousals and those flagged OAs or arousal breathing false positives or even if the OAs flagged are more central in nature than obstructive in nature.
More pressure won't fix or reduce the centrals and very well could make them worse.

The culprit is most likely the higher than normal altitude. It is quite common for people who go from a much lower altitude to have a truckload of centrals pop up. The altitude has less O2 content and makes people more susceptible to the unstable breathing that triggers central apneas.

There's probably not a lot you can do to improve things by tweaking the machine settings.

You can go here and learn how to identify awake/arousal breathing and see just how many of those flagged events might be real asleep events and some are awake false positive events. While it talks mainly about central/CA apneas...we can have false positives in any event category. It's not limited to centrals.
http://freecpapadvice.com/sleepyhead-free-software

It's the altitude that is the problem unfortunately and no easy fix at this point.