Never saw anything like that. However there is a small bug where the name of the current building project displayed above the city does not change until the next turn after you rearrange the queue.
Meaning, If the city is building barracks, then the city nameplate says 'barracks', then you reorder the queue so it is now building a militia, but the nameplate still says barracks until you press end turn. The production of the city for that turn correctly goes towards militia tho, its just a visual bug. Other than that. I never saw the queue change on its own.
