But are they George’s or Mouse-era Lucasfilm’s?
They were started under George Lucas and finished after he sold it. Weird.
Are you talking simply the scans, or do your sources claim changes were instituted on both sides of the sale?
The dates aren’t really my sources, they’re just from the resumés of workers people on here noticed a couple of years ago. Reliance MediaWorks started working on them in 2010 or 2011 and they were worked on as recently as 2013. It’s hard to say though with those resumés. They could’ve been referring to different projects on the same movies. I did hear from someone that the recent 4K work from Reliance wasn’t done in 3D though. Maybe the early one was 3D work and probably included more changes and the later one was a normal restoration. The possibility that more stuff was being done before George sold it makes sense because the blu-rays had very few changes and I’ve heard that the blu rays were supposed to have a lot more changes to the CGI quality. Devin Faraci said that the Jabba scene was different in one of the yet-unreleased versions of Star Wars, which would make sense if George had done more work to make the CGI appear seamless before he retired. I seem to remember Bill Hunt saying that Lucas was testing a CGI Yoda for Empire and Jedi for the blu rays. That’s harder to know for sure though since it was so long ago and nobody seems to even care about it anymore. The idea of there being more changes to future transfers of the movies has been unmentioned in articles that have commented on the OOT since the Disney-sale. I personally can’t imagine them releasing a new variant of the SE without including the OOT, but I like to prepare for disappointment when it comes to Star Wars. A lot of that is getting into wild speculation though.
This is unrelated, and I’ve said this before, but it’s slipped under the radar in these types of threads; a guy on neogaf’s forums let slip that the company he works for was asked to remaster Empire of Dreams in HD (it seemed to imply that it was the same company that mastered it in the first place) but Lucasfilm kept delaying in giving them the footage from the original films. He said he was worried that they’d just have to upscale those parts if they didn’t give them the prints. The fact that Empire of Dreams is getting remastered in HD, and by now it probably has been, is promising in my opinion. Why it was taking so long to get the OOT footage (the guy admits to not being in the loop on as to why) is another question.
EDIT: I just realized that in this wall of text I didn’t even answer your question directly. I don’t know that changes were made after the acquisition, but I personally doubt it. I think that if any changes were made after the blu ray, they were done on George’s watch. For what it’s worth, Disney certainly hasn’t been kowtowing to his “vision” regarding Star Wars with the sequel films.