Is Elias Mannix his own great great great grandad?

So, I know that Julian Harker and Elias Mannix are just one person. What still confuses me is that, in the original timeline where the loop is yet to happen, how did Elias exist? If he hasn't yet time-travelled in the past, how would it be possible for him to exist if he is his own ancestor?? Was there anything I missed in the series? Help.