I’m sure this question is answered somewhere very obvious, in the documentation, but I can’t seem to find it:
What is the difference between different /e/ OS versions: R, Q, Pie, etc.?
Are they based on different versions of Android?
Also, I notice some phone models are supported for the R (or Q) version but Dev only, not Stable. How is that possible? I would have expected the stable version(s) to have more, not less models supported…