I have the same question as mamatonny. Did you guys see changes in LUD before getting the welcome notice? or the welcome notice came directly to your mail?
In my case, TSC received my RFE on June 12 and the message saying that I would receive a written decision/ or written update within 60 days. I have seen updates on June 14, 15, 16, 17 (without changes in status) then nothing. I am very nervous as I am waitting for the GC to start my new job. (I did my finger prints code 3 right a month after I applied).
Mamatonny: can I ask? what kind of document you submitted per request? In my case, it was a waiver, form I-602.