Xiaomi is seeking more people to test Android 12 on its recent flagship smartphones. Currently, Xiaomi is only looking for those who own the Mi 11, Mi 11i and the Mi 11 Ultra. All devices must be enrolled on MIUI's global branch, too.
https://www.notebookcheck.net/Xiaomi-starts-Android-12-beta-recruitment-for-three-more-flagship-smartphones.578325.0.html