Wasn’t it reported somewhere back around December that Disney had in fact requested a copy of the LoC’s original '77 print of the film?
As I recall, the prevailing theory was that they could very well be using it as reference for what the actual content of the initial theatrical release actually was.
Yes, I posted that here. The colorist who posts on the Steve Hoffman Forums said that. I believe him more than most other people regarding Star Wars information. It’s also possible that they just wanted to consolidate files of all of their existing material, or something. It’s a good sign, but it’s not a guarantee.