Update to Customer Match Uploads in the Google Ads API and the AdWords API Starting March 1, 2021
https://ads-developers.googleblog.comIn order to make the processing of Customer Match user identifiers more efficient, Google is setting up a new upload limit for Customer Match upload request via Google Ads API and the AdWords API from March 1, 2021. There is no change to the limit of the overall Customer Match audience list size.