The sequence at AWS seems to be:

  1. Announce something in a blog post (sometimes get everyone really excited)
  2. Add access to that feature/setting in the AWS Web UI
  3. Add access to that in the official API
  4. Add access to that in aws-cli
  5. Add access to that in cloud formation stack creation

It seems sometimes weeks and months lag between steps (e.g. steps 2 to 3).