RE: What does this mean?
We4lcome to the forum.
Despite your very good numbers your flow limits are high and and you have some tendancy to a form of positional apnea, not bad, but let's try for a couple of simple fixes.
Flow Limits, EPR does an excellent job at reating flow limits and yours is maxed out at 3. So let's raise min pressure to 9 and we possibly go higher. This is what is driving your pressure higher. If increasing min pressure, and the below 'pillow modifications do not work we will suggest further actions.
Positional Apnea, in the form of "chin tucking or cervical alignment. The clusters of events that you highlighted are the signature of this. Nor now I want you aware or it and to look at your pillows. Change your pilloows to thinner/flatter, less firm, one vs 2, etc. The idea is to sleep on a somewhat flatter surface. Try this before we think about a collar.
Read the Soft Cervical Collar article linked in my signature. It will explain more and show actual results.
RE: What does this mean?
Side sleeping depends on how you sleep on your side. If you are square on your shoulder you need something firm to keep your head straight, and side sleeping does nothing to stop you from tucking your chin. When doctors talk about positional apnea they mean simply Back, R Side, L side or front. They typically (a very few do) do not consider or recognize any cervical position as being an issue. Your couch I'm sure is not helping.