https://wccftech.com/new-nintendo-switch-system-update-13-1-0/

Nintendo has rolled out Nintendo Switch system update 13.1.0, which adds support for the Switch Online + Expansion Pack.

The new Nintendo Switch Online tier is available now as part of Nintendo’s online subscription service, and today’s Switch system update adds support for the premium tier. In addition, this new firmware update further improves the general system stability of the Switch platform in order to enhance the user experience. Further details about the new system update weren’t shared. We’ve included the official release notes for this Switch firmware update down below.