Lots of times I take a nap after lunch. A good meal, combined with some alcohol, usually makes me sleepy, so I take a 1.5-2 hours nap. My AHI during that session is typically very low, and quite often zero. When I go to bed later that night (no alcohol), I typically sleep for another 6-7 hours, and my AHI is actually pretty good (anything between 1 and 2, in most cases), but always higher than during those sleep sessions after alcohol consumption.
It is also much easier for me to fall asleep after lunch (just a few minutes), while at night I am often struggling. Sometimes it can take an hour to fall asleep. I suppose the obvious answer is that a glass of wine, or a beer, after lunch helps to fall asleep faster.
It appears that moderate consumption of alcohol does tend to lower my AHI, and give me a good quality sleep (nap). During that short session, I do not wake up. It is typically a 1.5-2 hours sleep. No idea if I reach the REM stage or not, but normally I feel refreshed when I wake up. My overnight sleep is quite often a different story. I wake up multiple times, sometimes more, sometimes less, and the overall quality of sleep is not as good as during my naps.
I know one thing. I am definitely not going to drink more, in order to keep my AHI numbers lower (liver matters too ). Just wanted to share my experience with the forum.