distributions have nothing to do with QBI. all distributions from an S-Corp are treated as a reduction of the taxpayer's basis in the S-Corp (assuming it was always an S-Corp). if basis goes negative then the distribution is taxable as capital gain to the extent of negative capital. the actual QBI deduction is not figured at the S-Corp level only at the individual's level because such factors as filing status, overall taxable income, whether S-Corp income is from a general business activity or a specified service activity, wages paid by the business and the business tax basis of qualified property. in addition net capital gains and qualified dividends affect the computation.
the only items the S-Corp reports is its qualified business income
basis in qualified property
section 179 depreciation which is a separately stated item on the K-1 also reduces QBI at the individual level