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LibKey Discovery links in WorldCat stem from a data upload process that populates holdings on the LibKey side. That data is sent to LibKey automatically on a monthly basis. If you've had major holdings changes and want to update the holdings sooner, you may want to use the KB Downloads option to get a file of all your holdings and send them manually to Libkey/Third Iron.
There is more on WorldCat Discovery integration of LibKey/Third Iron links.