My experience
In my case, I have filled the AR-11 form and sent to London, KY each time (2 times I have changed) I changed my address. However they didn't updated in the USCIS database. I had to again sent another copy to London, KY and to my attorney's office to file the address change. First time it worked. Second time my FP notices were NOT delivered to my new address because the post office didn't deliver when there is a forwarded address; Again I had to go thru via my attorney's office to file it. This was happend 6 months back. Recently when I was trying to enquire about the EAD renewal, call the VSC service center phone and when spoke to the customer service rep they told me that even we fill the AR-11 form and sent to London, KY its our responsibility to call the service center and get it updated by speaking to a cs rep! I don't understand then why we need to fill AR-11 and sent to KY when they are not doing anything with it. Instead, USCIS should be able to provide us a website link where we can update our changed adress online or AR-11 form app should be entered online so that we get a conf. number & the details are readily availble to them for reivew..