Just a heads up. I just noticed that the announcement that went out for 12.8.1 included the new mdadm attribute. But my Pull Request for this is still open. However the doc team merged my PR into the the chef-docs repo related to this change so I think things got out of sync. I referenced my code PR in my doc PR hoping that the change would be coordinated. So those doc changes, and related release notes should probably be pushed to 12.9.x and the blog post updated to remove that bit.
David