Some people are saying that the new 4K master has more recomposited matte paintings and such than before, but I can’t confirm that one at the moment. So if that’s the case, it would mean more work for authentic despecializing.
No, just mix in the previous version for those shots. If you are after 4k, your choices are few, but if you are after HD, there is the new one, the BR, the HDTV, and the film scans. The effort Harmy went through for the original despecilized is no longer really necessary (unless you want to make the 97 SE version, and those are coming).