https://jfrog.com/blog/into-the-sunset-bintray-jcenter-gocenter-and-chartcenter/

To streamline the productivity of the JFrog Platform we will be sunsetting Bintray (including JCenter), GoCenter, and ChartCenter services on May 1st, 2021.

I think GitHub Packages is the best option for now and that would incentivize moving off of Travis, too.