In the episode "Because you Left," Richard helps Locke with his bullet wound in 2008 or further in the future. This is true because Richard mentions "They are already home." Don't believe me then watch the scene again. Anyway I think this clearly implies that in the time Richard helps Locke, the oceanic six have already made it back to the island.
Anyway if everyone agrees me with, someone should fix the date on the Because you left lostpedia entry.