I've had similar problems but I wasn't sure if it was due to the updates. My sot reduced to about 5hours and even less sometimes.
I checked the forum and tried the battery calibration, it took 8hr+ to charge it to 100, which was weird in itself but my sot improved to around 7hours.
But the charging was still a lot slow, so I tried the ampere app and tested the charging amps. Discovered it was (max) 390mA. Which is pretty low. That's why I didn't get "charging rapidly" when under 80%. So I changed the cable and now it gets a little over 1600mA (max), the "charging rapidly" returns as well. Did the calibration again, around 3hours to max charge this time.
Been getting around 10hours+ sot from 2 days now with around 3 hours of casual online games. Maybe would help you too.