A vivo X20 Plus variant has recently received 3C certification in China. The listing reveals 'vivo X20 Plus UD' moniker. The 'UD' part in the moniker has triggered speculations that this might be the first phone to feature an under-screen fingerprint scanner. Of course, nothing is confirmed at the moment, meaning 'UD' could turn out to be referring to something completely different. But we already know vivo will be the first to launch a phone with under-display sensor and a new version of its flagship seems like a logical choice. The phone is coming at CES, which is less than a week...
Source: https://www.gsmarena.com/vivo_x20_plus_ud_gets_certified_in_china_could_feature_underscreen_fingerprint_scanner-news-28961.php