Also Xiaomi released the second develop rom on 05th August,
https://xiaomirom.com/rom/xiaomi-12s-ultra-thor-china-fastboot-recovery-rom/#%E4%B8%8B%E8%BD%BD-%E5%B0%8F%E7%B1%B3-12s-ultra-%E5%BC%80%E5%8F%91%E7%89%88%E5%86%85%E6%B5%8B%E7%89%88-recovery-%E5%8D%A1%E5%88%B7%E5%8C%85
I am using Mi11 Ultra, updated to the 21.12.8 both first version and reuploaded version. So fur smooth, but I find that the Miui+ beta is not working can not connect to the computer. Also the "Permissions Details" when you pass on it no response.