@stevekewley
(a) If the under-reporting is because of a missed 1099-INT, then the AUR system may flag this as "under-reporting" of income and it is then possible that the human intervention result in a CP2000 letter to you.
(b) general guideline is if the changed/updated income does not result in changed tax due , then there is no need for an amended return.
My sense is that a $17 increase in taxable income is unlikely to increase your tax liability by more than a few dollars and therefore IRS may not proceed with demand to pay. However, I would prepare an actual amended return and see if the result is significant ( say greater than US$10) underpayment. And then decide if it requires filing or not. Also include in your computation of liability , the interest charges for underpayment.
I hope this helps
