TDK UHD was released a couple of days ago. I do not have a 4K Blu-Ray drive and I’m not even sure my motherboard would support the protection on the disks.
However, I have heard the following about the new transfer. 1) The color timing appears to be much more closely in line with theatrical prints. I’ve also found a few screenshots which look nothing like the BD version. 2) Edge Enhancement is not apparent if not non-existent in this relates. 3) Finally the bad news: The 1080p BD included is still the same the disk.
It looks unlikely that WB will release a proper 1080p now. That being said, when the day comes I shell out for 4K, I’d still like to insert the full IMAX shots in the film composited with the 4K version. It may not be possible given some scenes are only on the DVD, but I’ll still give it a go.