(Spoilers for Season 10!)
After the events of The Pegasus Project, Ganos Lal (aka Morgan le Fay) is exiled from the Milky Way and Pegasus galaxies to the Ori home galaxy, due to her marginal intervention in the human-Ori war.
Half a season later, in The Shroud SG-1 sends Merlin's device — the Sangraal — through the second Supergate to the Ori home galaxy, and it is later confirmed by Ba'al (having taken Adria as a host) that this action was successful in wiping out the Ori. Recall that the Sangraal is a weapon that destroys all ascended beings.
But in The Ark of Truth we see that Ganos Lal was "alive" and well, chilling out in the Ori home galaxy. Good thing too, seeing as she was then instrumental in the defeat of the now-ascended Adria.
How did Ganos Lal survive Merlin's device? Did it take the Ancients a whole half season (six months in-universe, perhaps?) to get around to shipping her off to the Ori home galaxy, such that SG-1 had already killed the Ori by the time she arrived? Was this ever explained in dialogue or in production interviews?