I agree with email - - but for another reason. You have a copy of what you actually said - - not what they wanted to hear! And, if you are lucky enough, you can also verify that they opened the email.
Just sayin - - - - -
And we are supposed to "verify" the accuracy and "acceptability" of clients receiving EIC or we will be fined.$500!!
It does not take a very skilled program writer to look for duplications of an address. The IRS is a dichotomoy of dichotomies!!