One of the most frequent missions given by the marshall of a realm is "X requests that you join his army with at least Y troops". The time to do this is three days, if you don't find the marshall the quest fails.
This sucks as failing this quest is quite easy and happens often as the map is quite large and if you're on the wrong side of the map, well ...
It wouldn't be quite so annoying if there wasn't a negative achievement connected to failing quests and this adds to it.
In principle I'm fine with how this works but three days is way too short. Five or seven would be better.