Dantelh
While helping Lady Tylora retake Tolrania, I stopped in Vinica to distribute fiefs among the rebels. I gave Starade to a lord, but after exiting the dialogue, I was greeted with a plunder menu for Vinica, and how I had "taken" it. The issue here is Vinica belonged to Elintor, who we were peaceful with, but not long after.
For context, I had just given Tylora a castle but she didn't leave my party, and I was in the town screen when I was distributing fiefs.