Xiaomi continues to push updates to the Mi A1, its nearly three-year-old handset. The device was Xiaomi's first Android One smartphone, a program that guarantees at least two years worth of OS upgrades and a third year of security updates. The Mi A1 has been upgraded to Android 9.0 Pie since Xiaomi released it on Android 7.1.2 Nougat in September 2017, so it will probably never receive Android 10.
With that said, a new update has been pushed to the device. Called V10.0.23.0.PDHMIXM, the update is only available for those devices that have been enrolled on the global branch of MIUI. The update is rather small, with the OTA hosted on Xiaomi's servers only being a 39.2 MB download. You can also grab the full recovery build if you prefer, which is a 1.1 GB download.
V10.0.23.0.PDHMIXM principally upgrades the Mi A1 to the July 2020 set of Android security patches. However, Xiaomi claims to have also "increased system stability" and "reduced system lag". It has now clarified what it has done to deliver these improvements though, so your guess is as good as ours.