I can confirm...
In January, we originally had row 44 for the FRA-DEN segment, but then I asked for different seats and we got up near the front of Y. When I looked at a seat map in the paper timetable, I noted to my wife that our original seats were second-to-last row.
I actually found the 340's Y seats to be a lot more comfortable than UA's 777 non-E+ seats.
Cheers,
Lawrence