Following AmyC's excellent advice with a little reasoning, the problem was completely solved. The solution was to delete all previous responses to the Form 8853 interview and to follow this with redoing that interview with a new set of more appropriate responses. TurboTax not "forgetting" what had been mistaken answers was the cause of my very significant increase in federal and state taxes.
As advised in previous questions about deletions on this site, using the Forms tab, I went to Form 8853, p2 and Schedule 1, line 8e and was able to blank out all previous responses. Then, with neither accelerated death benefits nor per diem (or analogous "other periodic basis") payments, I answered line 17 with a 0 (zero) and left the answers to lines 18 - 20 blank. The correct information for lines 21 -24 mattered not at all, other than to fill space, as did the resulting line 25, because TurboTax wisely left line 26 blank and consequently Schedule 1, line 8e blank. Hurrah. No additional income.
I think all of these problems could have been avoided if the IRS had created separate sets of Form 8853, p. 2 questions for per diem payments and for reimbursed payments.
