There are three major calendar systems in use in Arrylon today. It is usually good form when listing a date to also list the referent it belongs to so that confusion is kept to a minimum.
The designation EC refers to the Elven Calendar. Elves measure years in ages, so the date written on the elven calendar is 2595 III (EC). That is, year 2595 of the Third Age, Elven Calendar.
The other races do not divide history into ages, instead referring to the Great War of the past. PW refers to events prior to that war (Pre-War), and WR references events after the war (War Reckoning). The current date of the campaign is 3280 (WR).
Another Calendar used is that of the dragons. It is mainly used by the mythical Dragon Council, and in thaumaturgical circles. It refers to the year the dragons were created and brought into being. Years prior to that date are negative (as in -1260 DC), while years after that are positive (4388 DC).