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A supporter (identified by their email address) cannot enter a Welcome Series type of automation more than once, even if you stop and re-launch. However, for the Engagement types, such as birthday automations, they can. Additionally, you may leverage the REST API to allow certain supporters to enter a particular automation more than once (but at a maximum once per day), such as to support recurring gift notifications in advance of billing.
A duplicated automation would clear its memory of who had entered.
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What are the differences between the Welcomes Series automations and Engagement Automations?
Supporters can enter Engagement automation types more than once
Supporters can enter Engagement automations types even when they’re active in another automation (regardless of the account preferences)
Supporters will continue to get broadcast emails even if they are active in an Engagement type automation (regardless of the account preferences)
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