The Stable update V12.0.2.0.RCXMIXM has been officially released for Redmi Note 8T (codename is willow). Before updating, please make sure you have downloaded the exact ROM matching your Xiaomi phone/tablet. In Fastboot mode, you can check model code by typing fastboot getvar product in cmd/shell.
The firmware files posted here are all official Xiaomi MIUI or HyperOS ROM, xiaomiROM.com do not own and never modified those firmwares，you will always download the file from Xiaomi server.
You may interest in those contents: Redmi Note 8T ROM Topics Xiaomi Devices Index
Download Redmi note 8t (willow) Global MIUI 12 V12.0.2.0.RCXMIXM Recovery ROM with Android 11.0. Firmware size is 2.5 GB.