How does the in-game time and the day/night cycle work?

Solution 1:

Yes, the game does follow the local time that your console or PC is set to. Not only that, it matches the sunset/sunrise times based on current time of year/month. Pretty cool. But sucks if you only get to play at night.

Solution 2:

I think it relates to the story progress.

Everywhere that you travel to after the game is complete will be day.

Fast travel during the story and the time of day stays at that story point.