https://www.theverge.com/mobile/2019/3/6/18253804/pixel-3-xl-repair-solution-google-mail-in

Google has updated its US-only repair service to include the Pixel 3 and Pixel 3 XL as being eligible for mail-in repair. The inclusion of its third-generation Pixel phones comes several months after their October 2018 launch. Until now, owners with broken Pixel 3 phones had to resort to third-party repair shops, like uBreakiFix. Walk-in services might be more convenient for some than mail-in support, but it’s better to have more options for fixing your phone.

As noted by Android Police, Google’s repair service landing page is in a confusing state, currently stating that the Pixel 3 and Pixel 3 XL are only eligible for walk-in services, even though that’s not the case behind the scenes. According to a statement from Google, it’s just still in the process of updating the language on the page.