This one's simple, but since the community Rules QA is broken and there are conflicting rulings being given, I'm posting here.

Does Cast through Time successfully rebound a spell that exiles itself such as Time Reversal? Either way, why?

Nope. Rebound only works if the card would go to the graveyard while it's resolving. Something like Time Reversal exiles itself as its resolving, so it won't go to the graveyard, and rebound will not apply to it. So you will not get to cast the Reversal on your next upkeep.

702.87a Rebound appears on some instants and sorceries. It represents a static ability that functions while the spell is on the stack and may create a delayed triggered ability. “Rebound” means “If this spell was cast from your hand, instead of putting it into your graveyard as it resolves, exile it and, at the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.”

Nathan Long
Wizards.Com Boards NetRep