Michael and Walt do not appear on the flight in the "flash-sideways".
Due to a technical problem, Elizabeth Mitchell had to fly from Vancouver (where she was filming V (2009)) to Hawaii for one day to re-shoot the goodbye scene with Josh Holloway.
This is the first appearance of the flight attendant Cindy since season 3.
Here Charlie repeats the same line as what he said in the first episode of the show: "Terrific."
In that episode, he is facing possible death. This time, he was just saved from death.
In that episode, he is facing possible death. This time, he was just saved from death.
Although credited in the show, Emilie de Ravin (Claire Littleton) doesn't appear in the episode.