@lodhi
For me, I installed focal from the first download on the dev channel, and I can tell you that most of the problems that existed have been solved. I have the same device, pixel 3a xl a question, to make sure that the p3a xl works with a single SIM Do you see two SIM like my?
2023-02-23T12:06:05.130Z.png

@lodhi Please note going back and forth from 20.04 to 16.04 may throw up some issues. Treat them as 2 different OS. The apps can be completly different as is the OpenStore the main idea is that when you move you stay there.
My 3a had a few issues with installing after a few back and forths. There will be another RC soon for 20.04 and I would recommend that for the 3a which runs great on 20.04.

@Mark-Muth - Libertine in Focal is working well for me on my Volla Phone now, it just took multiple tries for me to get it installed (I ended up having to use the Terminal instead of the Systems Setting gui to get it done).

Best regards,
Steve Berson