MIUI 15 Alpha builds spotted online ↺
MIUI 14 arrived in mid-December 2022 and, depending on the device that uses it, might be built on Android 12 or Android 13. Fortunately, it looks like MIUI 15 will use two Android versions as base as well, so many older handsets will be compatible with it after launch. Obviously, it will take some time until that happens, since the next-gen mobile OS has just been spotted on Xiaomi's test servers in the Alpha testing stage.
According to Mi Code (quoted by Xiaomiui), the versions spotted on the test server are labeled 23.5.22 and 23.7.2. Based on these numbers, it is rather safe to assume that development began in May, since 23.5.22 should have been ready for testing on the 22nd of that month (the number format is YY.MM.DD, or YY.M.DD, in this case). Since it is too early to talk about individual specs and features of the new OS, "improved animations" and "various innovations" should suffice for now.
The information available on the test server also includes a reference to "garnet" which is known to be the codename of a model from the upcoming Redmi Note 13 lineup. Its specs are not known yet, but it is expected to be available in China, India, and the rest of the global market. Since MIUI 15 is already available for it in this early stage, it is safe to assume that the Redmi Note 13 family will launch with MIUI 15. Remains to see if it will show up at the same time as the new software interface or after its introduction, which should take place at the end of this year if everything goes as planned.