Apple push notification service certificate expiration

The certificate in question revolves around the following:

apns:com.apple.alerts

I'm of the mind that this is something that has been removed in one of the feature 'cullings' of the the OSServer? Otherwise for the life of me I can't find any certificate that is near expiration anywhere.

We're using the OSServer app (v5.10) as the MDM/Profile manager with Apple School Manager.

Anyone care to clue me in please?

thanks

Andy