Where is Daniel Faraday?

Does anyone have any ideas as to where he is? We saw that he was a construction worker for the DI...was he tampering with the construction of the orchid? I have heard a theory about him traveling time to save charlotte, but how would he go about doing that? He wouldn't be able to bring her back to 1974-7, right? So would he have to just stay in the ancient time period? I miss him.