FYI, here’s MisterLime’s (Kino Lorber rep) response to my question in another forum:

MisterLime, many folks have been asking this very question on several forums over the past few days. Will the KL release of the US theatrical cut be sourced from the 2014 4K master (used for the 2014 MGM BD) or a new 4K master? If the 2014 4K master will be used for the US theatrical cut will the image be altered in any way in terms of color, saturation, contrast?

Also, what is the source of the “M.O.S. Deleted Scene of Blondie in the desert finding skeletons”? Did you find this previously unseen footage in the archives or elsewhere?

MisterLime’s reply: The 4K master will be the same master, we’re looking into the yellowishness of the master and see if we can make some improvements. We’ll make further announcements later.

MGM found the M.O.S. deleted scene and offered it to us as an extra, that’s all I know.