I can understand your frustration. However, we have started doing internal beta testing for the next release of X, Pro and Cornerstone that's broadly going to be one of our biggest releases ever. The focus of this release was stability (bug fixes), performance, and usability improvements. It also includes Yoast SEO compatibility with Cornerstone i.e Allow Yoast to analyze pages and posts made with the content builder.
After internal beta testing we plan to do a beta testing with close group of public users and after collecting the feedbacks and working on them, we hope to release for everyone.
At the moment I can't give you an ETA but can assure you that we are fast-tracking every thing and very soon we will launch this update.