A12 has some issues with the way I set the phone up. I'm getting no alerts on some app (Whatsapp being the main one). None of the launchers I use will run under A12 (Poco/Mint) they give show a black screen. Custom ring tones don't work. I've been using the same alert tones for about 6 years and don't want have to start using new one.Why you want to go back on A11?