Hi Jfrench55,
Welcome to Apple Support Communities. We understand that you're having an issue with your Mail app after updating your iPad Air. We'd like to help.
Does this happen with one or more than one email account? Have you tried to connect to Wi-Fi to see if the mail loads then? This can help isolate this issue to the network you're using.
In the meantime, these steps can help:
If an app on your iPhone or iPad stops responding, closes unexpectedly, or won’t open
If an app on your iPhone or iPad doesn't work as expected, try this.
1. Close and reopen the app
Force the app to close. Then open the app to see if it works as expected.
2. Restart your device
Restart your iPhone or restart your iPad. Then open the app to see if it works as expected.
3. Check for updates
To see if updates are available for the app, open the App Store, tap your profile icon, then scroll down to see if updates are available. If updates aren't available for the app, update the software on your iPhone or iPad.
4. Delete the app, then redownload it
Delete the app. When you do this, you might lose data that was stored in the app. Then redownload the app. Then check to see if the problem with the app is fixed.
If you continue to have issues, let us know and we'll see what else we can do to help.
Cheers!