I agree, this could one of the reasons, another could be for people like me who have a lot of travel in the last 5 years.It's possible but it doesn't explain why some newer applications in the queue are processed before older ones.Take a look at the tracker, there's absolutely no logic in the processing times.One theory I have is that there are multiple queues, with each queue assigned to one officer and maybe some officers clear their queues faster than others.