That's how it shows up for me at least. Reduced aspect ratio and the top/bottoms of images are cropped to a standard size. I have been needing to wait a second for the image to fully load it's full format rather than needing to interact with a post though - it just happens automatically when it's in view on the screen.
For me it only changes if I touch the pic itself. If I scroll the post by other means, the ratio remains wrong. Was never an issue until the latest few versions of Jerboa.