Anyone know what is going on in Philadelphia Backlog center?

what kind of order does the center regard to the priority? My case was ted in Aug, 2004. I found out quite a number proved cases from 2005 according to the tracker database.(http://trackitt.com/usa-immigration-trackers/philadelphia-backlog-tracker/) What is happening in the center? They don't follow FIFS? Anything we could do except waiting? Thanks!