Board Thread:Spoilers!/@comment-6175354-20141215234519/@comment-24674051-20150318152453

I don't think any time is too early to introduce the character, even if they don't reveal the full details for a few episodes. There is precedent for that already on the Show. When August came to town, it was several episodes before we finally found out that he was, in fact, Pinnochio, and had been sent with Emma through the Wardrobe. And Neal was seen in "Broken", made his first appearance in the flashbacks for "Talahassee", before we finally meet him in "Manhattan" and discover the rest of the story, that he is, in fact, Baelfire, and therefore Rumples son.

So I would say any character that is introduced at this point that we have very little information on is a candidate to be the Author. That would include Agnes Bruckner, since we do not have confirmation that she is playing an Adult Lily, just a lot of speculation.