User blog comment:FairyRaven/Fairy Tail Chapter 426: Black Heart, Review and Commentary/@comment-25111584-20150401185614/@comment-25111584-20150403164410

@anon: Ummm, you seem to be misunderstanding something. Look at the pic I linked in my original post. Gray kills Frosch in Timeline 2, not in Timeline 1, where F. Lucy comes from. The Dragon Invasion does not take place in Timeline 2 (F. Rogue's Timeline). Timeline 1 Lucy (F. Lucy) is able to close the gates in time. Then Acnologia goes on a rampage 7 years later in Timeline 2, which is why F. Rogue comes back to Timeline 3.

Btw, the Timeline thing I wrote is not actually a theory of mine. That's how Mashima has actually explained it. Again, look at the pic. Actually, my original post is also not a theory, it's just an observation about how Mashima has woven the story now. ;)