The instructions of Form 5471 "Where to File" says the form needs to be attached to the tax return.  Last Friday 9/15 by midnight, I just E-filed my first C-Corp tax return Form 1120 including Form 5471 (it was a rushed time to work with the CEO together, and E-Filed by midnight), and I forgot to print the Form 5471 and attach it as a PDF attachment. 

Normally if a PDF attachment is required, ProConnect would give me a warning message and e-File button would not be available. But this time, the E-File went through without the PDF attachment Form 5471.  I thought I probably needed to amend the return after it was accepted to re-submit the PDF attachment. 

This morning I called ProConnect help and we looked at the tax return together.  I was told that Form 5471 was already submitted to the IRS and no need to be submitted a second time - she was certain about this because she saw Form 5471 was generated within the ProConnect Software and was available for partial print. 

I was relieved to hear that, but after the call, I remembered Form 7203 was also available for partial printing, and was still required to submit as an attachment.  So I can't help become worried again and wonder if Form 5471 was actually submitted in my case.  

Side fact: before calling ProConnect, I actually called the IRS international tax law phone number to ask if I needed to amend the return.  I was told the IRS personnel are not allowed to answer Form 5471-related questions, as the whole agency was not trained with this tax form and was not allowed to give out advice.  She suggested that I should ask this question to paid professionals.  

Anyone who filed Form 5471 before?  This is such a screwup for me and it won't happen again.  

Thank you in advance!!