As far as I can tell, we had no server degradation or downtime. Can you let me know how you are sending the notifications?
As for checking the status of push notifs and our other services, you can check here: https://status.expo.io/ specifically the Push Notification Broker.
We are sending notification by posting request to https://exp.host/--/api/v2/push/send with payload.
It is working now (since yesterday) so I am little confusing. (I am not sure what was the problem )
But thank you for telling me that there was no server downtime, and about https://status.expo.io !