https://wccftech.com/the-witcher-3-nintendo-switch-30-fps-analysis/

The Witcher 3 on Nintendo Switch has been updated this week, and the update not only introduced new visuals options and more, but also performance improvements that make the game hit 30 FPS more consistently.

Digital Foundry took an in-depth look at update 3.6, highlighting how turning off all of the new graphics settings introduced by the update make The Witcher 3 hit 30 FPS consistently in most areas while in docked mode. Improvements are much smaller with the settings on and in undocked mode.