Decide How to Install Android Pie
The Galaxy S9 Android Pie roll out is moving slowly. If you're feeling impatient, you might want to download the update right now.
If you don't want to sit around waiting for the Over-the-Air update you can manually install the Android Pie update onto your device right now.
If you're interested in manually installing Android Pie, you should get familiar with the installation process right now.
If the process seems too complicated for your skill set, wait for the OTA.