The tie-in to a Darkseid plot continuing off BvS was already gone by this point, right?
I have a hard time believing it will be better than a few alternate scenes, I believe including a scene where Diana doesn't get rid of the bomb that blows up the museum full of kids. That was reshot by Whedon, from what I understand.
I still have a morbid curiosity since it will at least be more cohesive and I can't believe Gal would get involved if there wasn't something happening. Snyder has often had directors cuts of many of his films IIRC, so it seems like it would be on WB if they were willing to fund the completion.
There's a direct tie-in to the vision Bruce had in BvS, and then some time travel shenanigans similar to Endgame.