Hi, I'm asking in regards to how time in the game works as I'm trying to go for the: Survive until date 1776.6.6  in "Doom mode". And I'm wondering how many days is 1 year? or rather how many day/night cycles it will take?

there is 16 days in a month and 12 months in a year each day finishes after a day and night cycle so a time change is half a day