Perhaps the cover size needs to be updated, the covers calibre sideloads are kept as small as possible while still working -- to preserve space.
When new Kindles first come out with increased resolution, calibre might need updating -- happened for the PW1 as well, IIRC.
What is the max resolution of the new Kindle anyway?
Also, I am moving this thread to the Kindle forums so Kovid will see it.
