Based on:
In Turbotax 2020, My IRA Info Wks contains the following:
Part 1 Line 1, Total basis in traditional IRAs = 3,077
Part 1 Line 3, Basis carryover as of 12/31/2020 = 1,792
it seems obvious to me that Turbotax 2019 performed correctly (passed basis=3,077 to TT 2020) and that TT 2020 incorrectly reduced the basis by the amount of my charitable distribution (1,285) to 1,792 which was picked up by TT 2021.
