SG-1 Season 8 finale
As I understand that the timeline they started in very first episode don't exist technically because SG-1 changed timeline.
And thanks to alternate timeline there was possible to defend Atlantis with ZPM.
But If you consider SG-1's original timeline, Atlantis was probably destroyed.
And then Icarus mission in original timeline. Is it possible that they managed to pull-it-up this mission or this only happened because Atlantis survived in second alternate timeline?