Not sure if this is a bug, but it is extremely annoying.
What happens: Someone suffers an injury in battle. The stated duration of the injury is, for example, “2-4 days”. The duration may or may not then decrease with each passing day. Sometimes the injuries heal on their own, as stated. Sometimes they count off each day and then the day after “1-1”, they show up as “2-4” again and begin a new countdown. Sometimes they do not go below “2-4” for days on end.