For the Alliance Assault world quest, one has to kill Legate Favre. However his respawn timer is completely inconsistent. Last week when I attempted him, I had to wait about 10 minutes (or the entire duration of the buff). This week, I waited 12 minutes (had to get a new buff since the first buff expired). However when I was doing some research, the npc respawned within 5 minutes for the next player to kill.