Troops Teleporting During a Peace Period

I ran into this issue about a year ago and ran into it again last night in my current game.

The game has a 1-day AI peace period and a 3-day player peace period, typical AWC style set-up. I experienced this glitch as did two other players in the game. I took and AI city and because my alliance was desperately short the resource, I pulled back to allow the AI to retake it so I could capture it a second time for the loot. I pulled back to a location that was still in the city. When the AI retook the city, my unit was teleported similar to if a player in the other alliance had taken it. I trust this is a glitch, as it makes no sense during the player peace period. I understand contested cities and one side getting teleported if the other side gets the city when both sides are trying to get it first, but the AI shouldn't cause players to teleport.