My guess is that the first level cap raise will come with patch 2.2 to go along with the next part of Binding coil of Bahamut. If there's no level cap raise they my next bet is that it will only happen with the expansion (which I expect to be released next Summer).
You're aware 2.2 will likely be in Summer 2014 for all we know? I hope you meant Summer 2015 for expansion.

- Oct 28, 2003: North American PC ver. released.
Wiki says that too, but I distinctly remember it being December 28th or 29th 2003 that I could get the game, install it, patch it for 3 hours, then play. Zilart was already released, and the cap was 75.