It’s a bigger deal with Return of the Jedi than for the other movies, I’d say, since the frame discrepancy caused the sound to be in advance of the picture for over half the movie’s runtime. In addition to that, the audio was apparently already in advance of the picture to begin with, so the dropped frames made it even more off. Overall this is more about correcting existing sync problems, by using the more reliable reference which is now available.
It isn’t yet possible to tell exactly how far off the audio sync is for the other two movies, but I’m hoping to get some film print references for those as well. Even if they are not complete it should still be possible to get an exact alignment by looking at the mid-reel splices and seeing where the corresponding dropouts line up. I’m currently beginning the tedious process of converting the frame numbers for the reels into timecode that I can see in my audio editor, so once I’ve done that I’ll know exactly how the sync of Jedi is supposed to work.