This has nothing to do with pinning, but with versions. And that's how version comparisons work. Of course, wrongly versioned packages like in your example fail.
** Changed in: apt (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to apt in Ubuntu. https://bugs.launchpad.net/bugs/1787757 Title: pinning doesn't recognizes releases names Status in apt package in Ubuntu: Invalid Bug description: Because pinning doesn't recongnizes releases names and treats them alphabetically it fails knowing which package is newest. This failed because the alphabet has ended and release names started again with A, B... Eg: 13.2.1-1bionic seems as a downgrade for 13.2.1-1xenial when it's really an upgrade. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1787757/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp