I haven’t heard anything about that, but it wouldn’t surprise me.
I took a picture of a page in the 70s treasury edition issue vs the reprint and yeah, I see what you mean about the recoloring. Not just the coloring itself, but there are actual mistakes in the recoloring. Please excuse my poor photography:
The corridor visable above Han’s left arm is yellow in the reprint, and, less obviously, there’s less shading on R2 than the older issue. These are both reprints, but I assume the much older treasury size reprint issue is closer to the look of the original issue #5.