It will be on april 1st.

Patch notes:
New Open world content
New jobs
Myth cap removed
New zones with new fates for you to zerg
Fantasia added to game, can buy now for a low price of an arm and a leg
New primal for you to beat your face against for hours and later complain about lag and terrible players
Release of coil turn 9001 with ilvl666 gear