That version of Calibre is in Stretch. I suspect you have not yet updated to Buster or your upgrade did not go particularly well. I can confirm the new version for Buster, since I am running it. Note: sudo apt-get upgrade << Updates to latest versions in current release you have installed sudo apt-...

Hi Everyone, Looking in the repository, calibre should be on version 3.39.1 https://packages.debian.org/source/buster/calibre However, when I try to update it, the pi says that it's on the latest version of 2.75.1 pi@raspberrypi:~ $ sudo apt-get install calibre Reading package lists... Done Building...