So I recently started upgrading Caed Nua, and eventually I received word that trolls and oozes would invade my keep in six-ish days. I clicked "Resolve now", and defended it myself. I went to rest up and continue down some of the floors below the keep, and I hired some people to make sure my keep was safe. So, I went to the main hall, and to my surprise, the trolls and oozes respawned, fighting the people I'd just hired. I helped kill them, and walked outside once again to rest and regain my spells. Walked back into the main keep, and yep, there they were again. They continuously respawn in my main keep, even if I just walk outside and back in. :|