Board Thread:General Discussion/@comment-5252535-20131218021635/@comment-477304-20140208185007

Check the link again, the SoA director said it wouldn't replace the standard Sonic continuity, as in, it's not the same continuity.

Also, the Sonic Chronicles two years thing is common misconception; it was mentioned early during the game's development, but as the game got closer to release, it was no longer mentioned, nor is it mentioned in the actual game.