Interesting, as much as I'd like to play with it I have a shoot this weekend and I feel like I should not tempt fate. I look forward to some reports from others regarding stability and other perhaps undocumented improvements.
So far extremely impressed by the HEVC HLG mp4 72mbps (which is 10 BIT 4:2:0) nice dynamic range and very very clean - no noise in the shadows. This might be an interesting high quality low bit rate option, especially for long recordings.