WB now owns the rights to ALL the films. They brought EVERYTHING (including the music tracks and SUPERGIRL) back from England in late 1999/early 2000 to do the extended 152 min cut of SUPERMAN THE MOVIE and later the SUPERMAN II- THE RICHARD DONNER CUT. The DONNER CUT would have been released earlier, but Brando wanted mucho $$$, so they waited until he died and settled with the estate. The SUPERMAN IV deleted scenes would also have been released earlier, but there was much confusion to the music royalties and rights. This is one of the reasons I think the Metro Club scenes were not released.

Neither Donner nor Richard Lester had final cut say on SUPERMAN I-III (the Salkinds did), so WB can put out ANY version w/o their permission so long as they get what their contracts called for in terms of royalties and the such. It is just a courtesy and respect to ask for the director's support and backing, but it is not needed. I assume that once Donner dies we'll get all we want, as was the case with Brando and his SUPERMAN II/SUPERMAN RETURNS scenes.

As mentioned, the AMC airing was the 2001 extended 152 min version released to DVD and blu-ray.

ALL the footage is at WB in Burbank, though it has not been "restored" or cleaned up (just stored away safer than it was in England in a storage unit collecting dust and humidity) and would be done so only as needed.