2 years from August 2019 should be 2021 August . But see
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its latest security patch is January 2021 which is not even 1.5 years after its launch. About 2 major OS update , it has got only one Android 10 and possibly that would be last
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I am quite astonished by the fact they provided miui 12 to RN4. Either RN8 users are not that lucky as RN4 users or Xiaomi got slowed down regarding updates