I am also having same battery issue. Before update my battery would last all day. I would get home and I would be at 75%.
I only text and do some occasional email. No facebook. No Instagram, No Snapchat. I uninstalled Facebook for good measure. Disabled all apps I am not using. Installed a dark theme. Went into Developer mode and set setting to only have 3 apps in background running ( I think that's what it is called). BAttery was awesome until update. I double checked my settings after the update and they are still set but battery is bad now.
Doing the Cache PArtition wipe now. Will see if that helps.
I am on AT&T. My sister who is on T-Mobile also noticed battery drain faster after update.
P213crew