So, just one last update on that slightly off-topic discussion from few weeks ago:
Following @Sean McCreary's suggestions, I was indeed able to build an up-to-date (unofficial) LOS 16.0.
It is really not that difficult - my very first build went through smoothly and relatively quickly (~ 12 h overall), even though the ressources I had assigned to my virtual building machine were not even remotely close to the recommended values (i3-U, 3 cores, 6 GB RAM, 300 GB hdd).
I'm now on Android patchlevel 05-05-2021, which does feel better, indeed. Thanks to @Sean McCreary's hint about ke