I know you're kidding, but for the uninitiated around here, Studio Distribution Services is the joint venture between WB and Universal for physical media distribution.
Digital copies are goofy, and very studio dependent. Up here in the Great White North, Paramount is iTunes exclusive for DC, and titles routinely upgrade to 4K on that platform. Up until last year, Disney was also iTunes exclusive, but they moved with the majority of the herd to Google Play, and...