My first thought was that a hard-fork of AOSP would be a much better solution than a Linux phone. But when you have locked down hardware, it doesn’t matter, because you simply can’t install it.
I still think a community fork of AOSP would be more efficient than Linux mobile.
Because there’s a very strict character limit on the Google Play store side for update messages. So if it’s a bigger update, all I can do is put a summary of the changelog there.