Hi, I checked and orientation is working. After changing the orientation you have to re install app.
Actually when we install pwa app. It saves manifest file in device and yeah it should automatically update after changing but as I think it still has issue. See the google docs ( https://prnt.sc/nz7pbv ). It says on desktop manifest does not update automatically but I think it has same issue on phone too. we are trying to get any solution.
Once we get any solution we will let you know. till than you just set the orientation whatever you want and change app name, your all new user will get updated orientation and may be already install to gets update as per google docs.