You know it say to send back the letter so I'm going to paper clip the little envelop on top of the rfe
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App sent: dec 3 Delivered: dec 7 to Vermont
bio: jan 4 (walked in dec 21 ) Trans from Vermont to Nebraska : may 21 Rfe: July 25 sent (letter July 29) sent back : aug 2
Uscis Received rfe: aug 5