somehow beatty got the wrong envelope.. Lets' Harvey off the hook.
I heard this morning that PWC keeps two sets of envelopes so that presenters who enter from one side of the stage or the other can pick up their specific envelope. One got missed in the rotation and was handed to Warren Beatty, it should have been discarded.
You could see that he was clearly confused when he opened the envelope and realized it was the wrong one. It looks like he meant to show that to Faye Dunaway, not actually have her read it, but she blurted out La La Land. There is audio that shows Beatty saying to her that it's the wrong envelope after the music plays and the crowd erupts into applause. Too late...