While not all Final Fantasies have events, quite a few these days do. This page serves as a handy event reminder, and lists other important dates and times for FFs such as game (and other product) release dates, online game maintenance periods and other miscellaneous things of interest to an FF fan.
Note that everything listed in the calendar starts with the short version of the name of the related FF title. You only need to look at the first few letters to find out what you need! Note that for games where a Japanese version and worldwide (English) versions are simultaneously running, the English version's tag will have WW added after the game's name.