Chrome OS Flex is currently released for early access testing and is not suitable for production use. CloudReady is available for immediate stable deployment. Google will automatically update CloudReady devices to Chrome OS Flex, when Chrome OS Flex is stable.
https://www.osnews.com/story/134571/google-unveils-chrome-os-flex-chrome-os-for-any-pc-or-mac/
https://www.theregister.com/2022/02/16/google_chrome_os/
https://support.google.com/chromeosflex/answer/11542901
https://web.archive.org/web/20220216210406/https://support.google.com/chromeosflex/answer/11542901