You can get the stamp at any USCIS office. I got mine in Philly in January with 2 days to go to expiration because there were no appointments in Boston in that timeframe and I was in Philly for work anyway. I took my RFE letter with me which was due a response in March. I'd say just take your RFE or extention letter you should be fine.
Help! Infopass out of state for I-551?
in Removing Conditions on Residency General Discussion
Posted · Edited by Wa&Ry
You can get the stamp at any USCIS office. I got mine in Philly in January with 2 days to go to expiration because there were no appointments in Boston in that timeframe and I was in Philly for work anyway. I took my RFE letter with me which was due a response in March. I'd say just take your RFE or extention letter you should be fine.