From the sound of things this is a minor issue involving some legacy code that would only show up in a few cases out of a large group of players. Still, the team is being very cautious and wants no hiccups as they move forward with tightening the AoC community. As a result, it sounds as though merges are going to be delayed a bit as the team does further groundwork to resolve these issues. Morrison says to expect merges to be happening well into January at this point, which is when they expect Update 4 to go live as well. Read into the full producer's letter for all the details.