The Mate X2 foldable phablet has been slated as the first device to see a public roll-out of Huawei's new in-house software, HarmonyOS. According to some knowledgeable Weibo users, the OEM has now started this process off. It seems the new system is still a developmental build, but is being sent as an OTA to the general public nonetheless.
https://www.notebookcheck.net/The-Huawei-Mate-X2-now-on-HarmonyOS-according-to-new-reports.535958.0.html