I have this movie as well. The bluray is encoded in the same aspect ratios as the IMAX theatrical release, which had 3 aspect ratios jumping around. If you look at reviews on Youtube, you'll find this a common complain for those who saw it on IMAX. When I look at the image before and after an aspect ratio jump, the shape of objects remains constant, indicating that it is actually the intended behavior.
The software on your PC must be self correcting the issue and use an uniform aspect ratio by cropping when needed.