Three kind of calendars are used in Two Clusters.
Those who live in “inner Sol”, meaning Venus, Earth, Moon, and Mars have a strong tendency to use the calendar that is widely used for our time.
However, those who live outside of inner Sol and those who stay in space mostly used what was called “universal calendar”.
A universal calendar was developed to replace the traditional calendar since concept of spring, summer, fall, and winter was long lost.
The universal calendar has the same 365 days, but concept of month is removed.
The day would be read in 1 to 365. For an example, Year 9599-200 would mean 200th day of year 9599.
This is de facto way of date recording for spaceships.
Another form of calendar is “seasonal calendar” which is often used by civilians in Andromeda cluster as well as Outer Sol (Jupiter and beyond).
There are four seasons, consisted of 91 days per a season, in the seasonal calendar. The last season has one more day to make it 365 days.
91 + 91 + 91 + 92 = 364
A usage would be like this: "My birth day is season 3, 87th day." & "That place is opening on season 1, 13th day."
On all official documents, universal calendar is used.
Wage payment period
Because of different standards of calendar, it is important for employees to keep track of their wage payment period. Some companies would pay wages monthly (30 days) while most government facilities pay wages seasonally (91 days). In general, seasonal pay is the most common.
The concept of holidays is often lost due to the fact that those who worked in space did not really have the luxury of taking days off without dire consequences.
Furthermore, powerful clans have their own holidays and ordered their clan members not to follow national holidays.
Thus, in Two Clusters, national holidays do not exist.
The only universally accepted day-off is Sunday of a week for civilians at least.
Festivals and special days
While there is no official national holiday, there are festivals and specials days. But these are different on each planet.
For good examples, “Burning festival” would be held on Mars whenever there was clear sky. Clear sky on Mar is a very rare occurrence. Therefore, whenever there is clear sky on Mars, Marians would prepare for the burning festival in evening.
For Venus, there is the New Year day on the 1st day of 1st season each year. It is considered a Venusian holiday which the O’ren and the Vues comply.
On Earth, the Bau’s holidays overrule everything. Due to the long history of the Bau, there are actually too many special days.