Mi Band Tools supports mi band 1s. I can measure the pulse, and I use other functions of the application. Why does sleep with adroid not work with 1s?
http://help.mibandtools.com/knowledge_base/topics/do-you-support-mi-band-1a-1-dot-1-slash-pulse-1s
From this page:
https:// Sleep as Android
" No public API. We are trying to reverse engineer it, so hopefully it will work eventually."
Greets
Unfortunately this is really not possible due to the firmware being different than other Mibands and being now a legacy product, there is low probability that the guys behind Mi Band Tools / Notify&Fitness are going to crack it.