Dig Into Android Pie Feedback
If you're still waiting for your Android Pie update to arrive, start poking around for feedback from fellow Galaxy A9, Galaxy A8, Galaxy A7, and Galaxy A6 users. This feedback will alert you to Android Pie's benefits and problems.
Installing the Android Pie update right after the prompt appears is extremely tempting but you should only do so if you're feeling one hundred percent confident about the move.
If you're feeling leery you might want to hold off and wait for more long-term feedback and/or Samsung's first bug fixes to arrive.