From UWIT’s eOutage Alert page:
Microsoft confirms email delivery delays
Updated 06/30/2016 at 12:06:30 pm
Microsoft Engineers are currently implementing a solution to resolve this issue which appears to be a wide-spread issue for many O365 Enterprise Cloud customers in North America. Some messages are currently being delivered, and Microsoft assures us that all messages will be delivered. Any unsent messages will stay in the Outbox and can be re-sent.
Next update: 06/30/2016 02:00 pm
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