Backdrop 1.13.2 - in Dashboard - under Available updates section there are listed all currently installed modules with text notes that there available updates, but the same "available" versions of these modules are already installed.
If click on Update link at Dashboard Available updates section the system goes to admin/modules/update with text "No updates are available for any of your projects."
Comments
There's an issue for it here https://github.com/backdrop/backdrop-issues/issues/3801. The issue queue is the best place for bug reports.