To manage iOS devices, you must first obtain an Apple Push Notification Service (APNs) certificate. An APNs certificate allows AirWatch to communicate securely to Apple devices and report information back to AirWatch.
Per Apple's Enterprise Developer Program, an APNs certificate is valid for one year and then must be renewed. The AirWatch Console sends reminders through Notifications as the expiration date nears. Your current certificate is revoked when you renew from the Apple Development Portal, which prevents device management until you upload the new one. Plan to upload your certificate immediately after it is renewed. Consider using a different certificate for each environment if you use separate production and test environments.
For more information, please see the Generating and Renewing an APNs Certificate for AirWatch KB article: https://support.air-watch.com/articles/115001662728.
APNs Certificate Expiration
The Notifications button in the header bar of the Console alerts you when your APNs for MDM certificates are close to expiring. This notice allows you to act.
For more information, see Admin Console Notifications.