TntConnect 3.5 r16 (BETA) is available, and it's compatible with the MailChimp API 3.0. MailChimp is shutting down older versions of their API as of April 2, 2019. So starting then, you'll need this newer version of TntConnect if you'd like to keep syncing with MailChimp. Please test it out and report anything you find. Thanks, Troy