(b) For the tax year in which such local law is enacted, no addition
to the tax shall be imposed, pursuant to subsection (c) of section six
hundred eighty-five of this chapter, through the operation of the
provisions of this section for the portion of the underpayment of
estimated tax as the result of a local law enacted pursuant to paragraph
(iii) of subsection (b) of section thirteen hundred forty of this
article.