I discovered a solution to this. NEVER schedule an email blast to be sent immediately. Always indicate the message is to be sent 5 minutes after you initiate the send. That gives you some time to stop the email message from being sent out. This will at least give you a chance to stop the mailing--assuming that Murphy's Law of Email Blasts takes effect. Murphy's Law of Email Blasts: A mistake in an email message will be detected or realized exactly 1 second after clicking on SEND.
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