In a case where an amount has been applied, credited, or refunded under section
6411 (relating to tentative carryback and refund adjustments) by reason of a net operating loss carryback, a capital loss carryback, or a credit carryback (as defined in section
6511
(d)(4)(C)) to a prior taxable year, the period described in subsection (a) of this section for assessing a deficiency for such prior taxable year shall be extended to include the period described in subsection (h) or (j), whichever is applicable; except that the amount which may be assessed solely by reason of this subsection shall not exceed the amount so applied, credited, or refunded under section
6411, reduced by any amount which may be assessed solely by reason of subsection (h) or (j), as the case may be.