Hi @MichaelY719 ,
Great question! At this time, the automation feature does not allow new emails to be tacked onto it once it is already an active series. We do have an open feature request for that, however, so I will go ahead and track it on your account. Our engineering team will follow up with you with any updates we have on that.
For now, the best thing to do would be to create a second series, and add the emails into that new series. You can activate that series once the contacts have gone through the first series, so they will begin receiving the second series.
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