One of my neighbors works for United IT here in Houston. This is a known problem. I've had it since the early days as well. Once the boarding pass is in apple wallet it does not automatically update. The boarding pass in the app will also not automatically update when changes are made. You have to manually refresh the boarding pass in the app and it will then update the BP in the wallet and if you have notifications turned on, you will get a notification. All great, EXCEPT for the fact that YOU have to manually update the boarding pass. I fly American and Delta and their apps automatically sync BPs even those in apple wallet. I've gotten into the MO of checking the monitors as soon as I clear security to see which gate to head to.