I found it. So, hopefully this is correct: On our 1040 Form, line 5a is now showing the total 2020 distribution, and line 5b is displaying the 1/3 CARES amount due for 2021. The total tax due appears to now be correct.
It's buried, and I can't even begin to describe the path to how I got there. Again, unless you painstakingly dig, you're going to miss it. TT is really remiss for not programming this in a straightforward manner in the income Q/A input sequence. As I said before, I suspect there will be a lot of people who took the CARES deferment, and like I did, assume the importation of a TT2020 tax return with a properly included 8915-E, would automatically bring that info into TT2021. In my mind, that's a pretty nasty (and potentially expensive tax underpayment) bug, and it does NOT come up in the completed pre-file Review.
