Xiaomi has rolled out another update for the Mi A3, its final Android One-based smartphone. With the Mi A3's third anniversary occurring later this month, V12.0.25.0.RFQMIXM could be the smartphone's penultimate update.https://www.notebookcheck.net/Xiaomi-rolls-out-July-2022-security-patch-globally-to-Mi-A3-as-smartphone-nears-third-anniversary.635033.0.html
What is your source for the claim "presumably on its penultimate update"? I ask this because the source you linked clearly states "last guaranteed update" and, incidentally, that would also be my expectation if Xiaomi's history in the Android One space was to be repeated.