Why does Fritz prefer underpromotion in this position? Why does Fritz prefer underpromotion in this position? How can underpromotion to bishop evaluate so much higher than normal queen promotion?

Can this be a bug in the Fritz 14 chess engine?
It's because 1. exf8=Q+ Kxh7 2. Rxd7?? would be stalemate. I think it is a even a theoretical draw after 1. exf8=Q+ Kxh7 2. Qg7+. Therefore 1. exf8=B+! (with check!) is better, since white then can keep an extra piece and win easily.

[FEN "5r2/3qPbkB/8/7P/8/8/8/1K1R4 w - - 0 1"]

1. exf8=Q+ (1. exf8=B+!) Kxh7 2. Rxd7? (2. Qg7+)