Ok, here is what I found so far, Golarion consists of 12 Months, each Month has 30 days except leap year which has 31 in Arodus every 8 years last one being 4704 AR.
Here is the questions I have:
1) Is Sunday, or Moonday the first day of the week It seems to be listed as Moonday but I have seen references from Sunday to Starday?
2) I assume Kingmaker happens to start 24th Calistril 4710 AR. What day of the week is that?
3) What is the Moon Cycles to know for encounters on full moon nights or new moon nights?
4) Does anyone know of any River Kingdom/Brevory Holidays?
If no official position stands I will of course make it up myself....