The change has ZERO impact on my 2017 IL taxes. From what I've been able to find I *shouldn't* have to file an amended 2017 IL form. Is this true, since it has no impact?
You are OK. The IL site
http://tax.illinois.gov/MyTax/IL-1040-X.htm
states:
Do I need to file Form IL-1040-X?
You should file Form IL-1040-X, Amended Individual Income Tax Return if
NOTE: If the federal change results in a refund, do not file Form IL-1040-X until you receive notification that your change has been accepted by the IRS.
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