The mail system migration will commence in 90 minutes at 6am PT/9am ET(US). All mail will be rejected for a brief period while the mail queues are drained. If you happen to send email during this time and receive a rejection notice, wait an hour or two before resending the email unless the rejection notice stated that it is being queued for further attempts to send the email.
I will send another email when the transition is complete and normal mail operations have resumed. e.
