Docker Enterprise Edition and SQL Server 2017

I’m trying to understand the relationship between Docker Enterprise Edition and SQL Server 2017. I’m already able to run a SQL Server 2017 container in the community edition, so why is Docker Enterprise Edition needed? Is it strictly for (production) licensing reasons? Is it because some SQL Server features (e.g SSRS, SSAS) are not available outside of Docker Enterprise Edition?

Also, I read somewhere that Docker on Windows containers for SQL Server 2017 is not yet GA. When will that become GA? Where should I be looking for that information?