softwareupdate --list-full-installers stops at version 12

As the title and the below image shows, when running a software update fetch command, the versions stop at 12. I should see up to 15. Any ideas? https://preview.redd.it/bgit8m30po9e1.png?width=1237&format=png&auto=webp&s=3820e7320be5a0fab569b2f0ac486d2f28a4c18c