Hey Michael. That configuration you’ve got definitely sounds like it could be an issue; while events can technically be scheduled to recur that far out we haven’t found most users do so, which would explain why this event hadn’t really come up before.
Are you in a position where you can test cutting those down (having the end in 2015, for example) to see if that resolves the issue? If you can confirm as much, I can see what the team can do to account for users with long-running events such as yours down the road.