If you have lump-sum income, you want your estimated tax payment to be in the same quarter as the income as @opus17 said above. The IRS addresses this by suggesting the annualized income installment method if the income is earned unevenly through the year. In your case, since the first conversion is occurring in the first quarter, I would include 24% of the conversion in your April 15, 2022 estimated tax payment.
@chen123
