Hello and thank you for your answers.
My main objective is to get rid of Android (except the obvious parts for the Halium container) on my device. Also I really would like to run close to mainline, but this is more a dream than reality.
With the addition of snap and easy integration of waydroid, I can seamlessly migrate over and use most of the snap programs I already use.
I know that I cannot do an "apt install whatever", this is a little sad but I know where it comes from.
I did not find some of my preferred programs in the Open Store or they where severely outdated (Element).
I am aware that the Open Store uses click (I think was the name) packages, and is therefore another format other than deb or snap.
Regarding the installation.
The installer does not state which version will get installed. This is what stopped my attempt, as is would like to know which version gets installed if I where to click on install
The installer mentions a specific stock Android version (for Halium) to be installed, which implies that 20.04 would get installed.
Then again, my target version is 24.04 and I am not sure if my device could be upgraded to reach this version.
I got the impression, that this is not quite sure, which I hoped to get confirmation here for.
I have no problem first installing the older version and then upgrading to the recent version, but would only do that if it is certain that it is possible.