Hi Urtė,
Thank you for reaching out. Regarding automatic updates for customer lists, you would need to implement one on your end since a scheduling feature is currently not supported in the AdWords API.
As for sharing userlists between accounts using the AdWords API, my apologies as this is also not supported. If you wish to learn if userlist sharing is possible via the Google Ads UI, you may get in touch with the product experts via the
Google Ads Community Forum for further guidance.
Best regards,
Peter
Google Ads API Team

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