Basically the title.
And how important do you really think Android version updates are. I don't use my phone for a lot more than podcasts, instant messaging, and occasional browsing on Firefox mostly with JS disabled and ad-block on. I have a 3 year old Android 7 device that looks and works just fine and see no reason to upgrade
I have a OnePlus 6T but I'm interested in Linux phone projects since I thought they died after Nokia merged with Microsoft. Android updates are mostly needed for security patches, there was a big Qualcomm security bug found recently.