The Star Wars Calendar

Beginning with the Proclamation of the Empire, on the one-hundred-fortieth day (I think) of the sixth year after the beginning of the Great ReSynchronization, the Calendar changed though not as much as one would believe. While the Year was reset, to 0 for the remainder of that standard calendar year, but the Galactic Standard Calendar remained based on the 368 day year of Coruscant.

The Festivals and Fetes

The first five days of the year are The New Year Fete week, a five-day festival that celebrates the new year. A second fete week, The Festival of Life, occupies the space between sixth and seventh month. A third fete week, The Festival of Stars, exists between the ninth and tenth months.

The Great ReSynchronization Calendar

The Great ReSynchronization was a 60-year effort to collate the myriad calendars used by individual planets across the galaxy into one cohesive calendar. The GRS calendar's months are seven weeks long, and each week consists of five days, resulting in a thirty-five day month. There are ten months in the standard year, and beyond the Fete Weeks, there are three holidays spread among the year. One is after the second month and another after the fourth month, with the final one being after the eighth month. What the Holidays celebrate are left entirely to the Planetary Governor to determine, they exist to keep time consistent.