I filed an 1040R in 2004 in error. I was working in the US on the OPT part of an F1 visa and should have declared myself to be a non-resident ("exempt individual"). Since then my status has changed to resident alien (switched to H1B). Is there any advantage or disadvantage to changing my status with a 1040X for 2004? I have contacted several CPAs but nobody seems willing to help me. Thank you!