It’s very impressive that they got such a modern process up and running in such a relatively short period of time. I understand the Arizona location is relatively new.
Yeah, they're essentially doing trials where Arizona fab provides small amounts of sillicon that's being validated against what Taiwan fab does. While it was planned for 2024 I'm guessing everyone thought it would be delayed. It's quite a big win for US, they're on track to secure domestic supply of fairly modern chips in case shit hits the fan in Taiwan.
Also, if interested, check out this documentary: https://en.wikipedia.org/wiki/American_Factory. Has a lot of interesting crosstalk between Chinese/American views on work and business.