Hello dear K-9 users! You probably got a suggested updated for K-9 to "Thunderbird Beta for Testers". This is just a metadata issue, which displays a wrong name and icon. The update itself is K-9 in version 8.0. You don't get automatically switched over to Thunderbird. This will probably be fixed in the next index update. In other news: Thunderbird for Android is available now on #FDroid ;)