I bought a Xiaomi Mi Band 1S one year ago solely for the reason of taking advantage of the “Early Bird Alarm”. This feature essentially tells the band to watch your sleep cycles 30 minutes before your set alarm and wake you up if it detects you are in a light sleep some time during this timespan (you probably knew this already, why are you here otherwise? ;-}). Sadly, Xiaomi removed this feature some time in 2016 without ever mentioning why or if it ever returns. As I don’t use my band for everything else, I recently decided to recover my “Early Bird”. I was successful and want to share all the actions I tried in case others have a similar need for returning their smart alarm. I assume these steps can be applied to other Mi Band versions (Mi Band 1, Mi Band 1S, Mi Band 2) as well.
Prelude: I’m not certain if every action is needed. I tried dry testing my changes but all changes failed the tests, including the (fully working) one I’m using now. So I advise on “live” testing every change for two or three nights if you don’t want to pull completely through with everything. If you find out only parts of it are needed, I’d appreciate if you left a comment afterwards.