I have 2 issues, quick battery drain and random restarts.
The upgrade is killing your battery...
If you use a CPU meter, you will see that the CPU is running higher than it should.
You can even use common sense to test that theory.. my phone only has a 1650mah battery or something like that. I am charging the phone is drawing 2.1A. With the phone on, it is taking 10 minutes or more per 1%, which means the phone is burning the power faster than it is charging (and yes, I turn the screen off and check every 30 minutes). I shut the phone off and the battery charges from 0 to full in less than 1 hr.
The update is causing the CPU or GPUs to run bonkers, and that is why we are seeing bad battery life.
Lithium Ion batteries have a finite charge ability and also degrade quickly when they get warm. You can only really recharge them about 500 times before you start seeing loss. Since the battery is quickly discharging, you are "burning" the number of charges on it.
Lithium Ion battery failure is also on a logarithmic scale and not linear. It will go from working to not, faster than it goes from excellent to good.