Those who build the foundation for the entire vibe and feel of the entire expac still get in touch with each respective micro-groups assigned on specific tasks and have supervision. There is a probably daily meeting as to turn in report of daily tasks, a mid week for team leaders across department and a weekly for the head of each team with a general meeting with higher ups. Specially now they have gated their features and are closely monitoring on live performance of everything for major/minor hotfixes some of the major work might be internally under rigorous testing.
I believe they have been working on 8.1 during the release of pre-patch content and during the course of the following weeks beta testing will be conducted for 8.1 features. Take note this raid would definitely have end boss cinematics as well.