As you know, Xiaomi has been releasing updates as Stable Beta first then full release recently.
This resulted in much confusion between users as they download a rom to update manually then the updater app doesn't allow to install it.

So, I have updated @MIUIUpdatesTracker, @XiaomiGeeksBot and xiaomifirmwareupdater.com to differentiate regular stable and stable beta roms. Stable Beta may be uninstallable using the updater app, so download it if you have a custom recovery only.