The Criterion release was from a 4K digital restoration and you have an audio option for 5.1 surround remix.
This 50th Anniversary 4K restoration was created from the 35mm original camera negative by the Criterion Collection. The colour timing was done by referencing a previous colour grading that had been supervised by Grover Crisp at Sony Pictures and approved by director Mike Nichols. The 5.1 surround-sound remix, approved by the director, was created from the 35mm magnetic tracks and the original soundtrack recordings at Chace Audio.
This appears to be a UK release. Wondering aloud who, if anyone, is handling an analogous release in North America. MGM handled the pre-Criterion releases.
I think MGM still controls the American rights, but the UK release would seem to be a response to the recent Criterion edition. Why would anyone bother putting out yet another American release so close to the Criterion?