Unlike many other games Lotro uses a manual process to transfer characters. There is a fixed upper limit on the number of transfers completed per day based on the number of employees available. Apparently the opening of preorders for Helms Deep resulted in a huge upsurge in requests. In a short order Turbine had enough requests in queue to keep their people busy for 2-3 weeks.
Turbine is working on a automated character tool. It is not ready.
Unless stated otherwise, all content in this post is My Personal Opinion.