Could someone explain how timekeeping works in this game? 
E.g. before rest at the stronghold, the watch says: 
Day 16, Hour 14, 14 Fonprima, 2823 AI 
  
then after 8 hours of rest: 
Day 17, Hour 22, 14 Fonprima, 2823 AI 
  
Shouldn't it still be day 16, or does the day not start on hour 0?