To add the second entry, click the Add another Recipient button on the Here's your alimony received info page.
In each case, enter the date of the original agreement. Marking the box to indicate that the agreement was modified after December 31, 2019 caused the alimony so marked to be excluded from income.
You are not fudging you answers. TurboTax is asking the modification question with respect to each portion separately. Only the entry without the modification box marked is includible in income. Because the entry with the modification box marked does not appear anywhere on your filed tax return, there is no need to actually enter it; you are entering it only for your personal records.
