Hi Vaun
We use the APIs to accomplish this and have them scheduled as part of our nightly/morning SSIS jobs so it's not a manual process. We export and clear the contact lists nightly and then import new ones the following morning. Here are the two we use for the evening cycle - I can't lay my fingers on the morning import API right now but could dig that up later.
/api/v2/outbound/contactlists/{contactListId}/export
/api/v2/outbound/contactlists/{contactListId}/clear
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Emily Kammerer
Ascendium Education Solutions, Inc.
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