On the assumption of a 3 month patch cycle and a 1 year expansion cycle, there would be no 2.5 patch. Omega or Ascians or any other manner of crazy shit (read: the primals we couldn't imagine which Yoshida spoke of) is a definite possibility for the finale of version 2, I'd say. If we cliffhang, it will involve Omega and Ishgard, I'm certain of that much. We already cliffhanged on the apparent death of someone significant, so i don't see that happening. The situation with Bahamut is the only thing I can see them tying a bow on. Everything else that is in motion has far reaching consequences. Ascians and primals because they never truly go away, CT because of the Void Gate which has been open for thousands of years.