Prior year safe harbor
If a taxpayer elects to have this clause apply to any taxable year—
(I) clause (i) shall not apply, and
(II) for purposes of computing any annualized income installment for such taxable year, the taxpayer shall be treated as having received ratably during such taxable year items of income and credit described in clause (i) in an amount equal to the amount of such items shown on the return of the taxpayer for the preceding taxable year (the second preceding taxable year in the case of the first and second required installments for such taxable year).