Because
For either paper-mail filing, or e-filing, NC isn't accepting any files until the middle of February, "currently" scheduled for 17 February....but that could change:
North Carolina Individual Forms Availability (intuit.com)
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The reason for the lateness, is that NC DOR won't be ready to take any forms until then....and doesn't really want anyone to try filing until they are ready.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
