I'm having the same problem. Turbo Tax won't let me change form 2210 AI line 14. When the program is calculating the annualized tax due for each of the first 3 periods, it looks like it is applying the same value for the enhanced senior deduction to all 4 periods (using the enhanced senior deduction for the last period for all 4 periods, rather than calculating what it would be based on the annualized AGI for each of the other 3 periods). I suppose we could fudge the entered AGI values for the 1st three periods to compensate for this, but I think Turbo Tax should either calculate the enhanced senior deduction based on the annualized AGI's for the first 3 periods, or let you change line 14 as called for in the instructions.
