The Redmi Note 8 remains stuck on Android Pie and MIUI 11, and it appears its journey towards attaining MIUI 12 and Android 10 has hit yet another bump. It's not the only phone in similar straits, however, with the Redmi Note 7's update also hitting a snag.
https://www.notebookcheck.net/MIUI-12-update-for-the-Redmi-Note-8-and-Redmi-Note-7-reportedly-delayed-after-hitting-snag.482110.0.html