This has been happening for months. The software usually is off detecting when I went to sleep, so I'll change it from "11:32 PM" to "10:15 PM" for example (IE adding MORE sleep time). When I do this my REM and Deep Sleep numbers significantly decrease, show up at completely different times, or sometimes completely zero out. I have a bunch of screenshots showing this if anyone in support wants them (and I can help file the bug with all the proper information).
Example from today:
Sleep was detected from 12:02 AM - 8:03 AM.
REM was 1h2m
Deep was 31m (mostly from 3:30 AM - 7:30 AM)
I changed my sleep start time to 11:05 PM (the previous day, 1 hour longer)
REM recalculated to 54m
Deep recalculated to 21m (NO Deep sleep after 12:11 AM)
Looking at my sleep stages before and after I changed my start time, I SHOULD have seen 51 minutes of Deep sleep after I changed my start time.
This is called an "indeterministic algorithm", which mean you get different results from the same data. Which is terrible for a product that calculates things.
