Duplicates get removed nightly, but we automatically de-dupe so we never send to duplicates.
If a record is in more than one "included" target group they will still only ever get the email 1 time.
Syncing happens on send from community so whenever you send a message you are sending to the most up-to-date version of the list. You can also sync manually whenever you'd like. More info on that lives here in the List Builder Lists section of the article : https://support.higherlogic.com/hc/en-us/articles/8631218987796-Higher-Logic-Thrive-Platform-Connection-Guide
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Tirza Austin
Senior Manager, Online Community
American Society of Civil Engineers
1801 Alexander Bell Drive
Reston, VA 20191
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