Odd is putting it mildly. There are frames within shots where the color correction doesn't even match up. Sometimes, it looks like they simply mis-selected their frame range when adjusting the color. The first frame of Leia in her cell before Luke rescues her is one example I recall. Accidentally didn't give it the blue coloring. Perhaps it was an ugly glue frame that just turned out totally different?
The last shot of the film, maybe about 5 frames before the wipe starts, also has a change in grading. As well as during the wipe shortly before, as Luke is exiting his X-wing. Probably a hundred more examples throughout the film.