I called TurboTax customer support, waited in queue, talked to an agent, shared my screen and showed the error on 2210 line 10 (doesn't match line 27 on for AI), and was assured that the team would investigate. This morning I got this email:
"
Thanks for letting us know about your issue with TurboTax. We apologize for any inconvenience this
caused.
We appreciate your patience while we looked into your issue. After completing a full investigation into your concern, it was determined this was not a product defect. Below is a link to the IRS Pub i2210 instructions. The IRS Pub explains the Annualization Income Installment Method:
https://www.irs.gov/instructions/i2210
We apologize for this. However, If you’re still having trouble
or there’s something else we can help you with, feel free to give us a call. "
hmmmm....
