I'm thinking now since the gross distribution occurred in 2024, Line 4a should be -0-.
One way to make this happen with my tax software, the amended gross distribution in your made-up 1099-R should be the taxable amount shown also in Box 2a.
Use "8J" as the distribution code, and check "taxable amount not determined" box in 2b. Do not check the IRA/SEP/SIMPLE box.
That would put the taxable part on Line 4b and zero on Line 4a.
TurboTax may handle such a 1099-R differently.
@txpharmguy0330
