This has happened to me twice now. Once on the lite version and now just on the full version for Ipod. I am usually way into the game, with many fish in my tanks. Both times, it has happen when I go to the Ipod time to advance it an hour and poof I come back to nothing but the start over story screen.

The full version is much buggier when moving the time up an hour. I tend to go back in time instead of up and lose things.