Android system battery drain

My android phone has heavy abnormal battery drains coming from Android system. **2000mAh and above on a single charge! I know for certain this is a software issue and not hardware.** Before I hit the sack. Battery was around 96%, next morning 80%! Normal overnight drains on my mobile model is 1-2%, I am having around 15%. 1. During sleep, All my radios are usually off (WiFi, NFC, Bluetooth, Data, location), except phone. 2. My phone seems to be in deep sleep a good portion of that time (See WLD statistics - attachment #1). 3. Android system sucks my battery during sleep and it was at 90% relative consumption when I woke up (See screen shot #1, **Android sys has consumed 1840mAh in such a short time span!! This is ridiculously high for a phone that is apparently in Deep Sleep!**) 4. Also attached screen shots from WLD for Summary, Kernal / Partial wakelocks & Alarms. 5. Device is rooted. 6. Google sync is off, Backup is off. I have searched all over. Read numerous threads from numerous forums. Some users have faced this issue on the same ROM while some others haven't. I have done my "homework". But this is one issue that I do not see any solutions wherever I look. I have searched days, not hours!! Hence I decided to post over here. This is my hail mary attempt at solving this. If the experts here can't solve it, then I guess it would be pointless to search anymore. **What is the issue that is causing this battery drain from Android System?** I have noted that many users using my model (Huawei Mate 8) do not face this issue, while some users do face it.