Originally Posted by
jackvogt
Well either way it will be E or F. No other concourses accept international arrivals that require customs and immigration. Honestly it doesn't matter where the flight arrives anyways. As part of international to domestic connection in Atlanta, you claim your bags and then recheck them to your final destination. In the OP"s case, they would just exit with their bags instead of rechecking them.
But it DOES matter because if it is E, then the OP's bag will go to the reclaim area instead of to F with the local traffic. If the OP picks up their bag in E, they will have to recheck it to get through security. Then the bag goes to LGA.