processing timeline and center handling the case

[moorthyak]

Hi - I filed concurrently i130/i1485 for my parents in Oct 2017. had rfe that we USCIS received in Jan 2018. Questions:

1) Does the processing go by i130 or i485? When i check online for processing times, should i look at i130 processing time or i485?
2) How do i know which field office or service center is processing the case

Thanks - i am based in NJ.