Form 1040X and New Unemployment tax law changes

Question....

 

I neglected to add my son's 1099-G on his return back in Feb.   NH never sent a hard copy and I completely forgot.  I then saw to amend the return (saw this early March), I needed to wait until 3/25 or so for form 1040X.   But now the unemployment tax law has changed and I did not submit 1040X yet.

 

Question is a follows:

1. I think I need to AMEND his return regardless, correct??  

2.  He DID NOT pay any federal taxes on his unemployment, and made $3840.   So I assume they will adjust and he may PAY now on the amended return, but then they will review his again and pay it back based on new law?  Regardless, they need to know about the 1099-G I failed to submit.  Is this correct?

Spoiler
 

 

Thank you