It's odd. After turning off BAP access to my contacts, my battery last much longer but I still randomly have BAP drain the battery but then I can go a few days without it using any battery. I check the Battery App Usage many times during the day trying to see when BAP is using power and can't narrow it down. Sometimes it uses battery in the morning others in the evening and then not for days but most often it seems to be using battery when I'm using Bluetooth or talking on the phone. I can always tell when BAP is using battery as the phone gets hot. If I catch when BAP battery usage is high, I turn the battery saver on for a few minutes which stops most Apps. Then when I turn off battery saver, my phone has cooled down and BAP App goes down on the list of battery App usage.
I'm at the point of considering doing a reset back to W8.1 then doing the whole W10 install process again to see if it clears BAP. The key is to make sure you don't even start up BAP after a reset. I opened the BAP App after an update a couple months ago to see if there were any new options to uninstall or turn it off but I didn't accept the Verizon agreement on the first page so I assumed BAP didn't start but now I'm thinking maybe it did. My current battery usage is reasonable now with BAP only periodically draining the battery so I guess I'm ok but my OCD kicks in and I want to fix it.
Question for you, when you started W10 recently, did you allow the BAP to set up during the start up process? If you did, that's your "bad" battery usage issue so you'll have to do a hard reset and start from scratch. If you skipped the BAP during startup and have never opened the BAP App and are still having battery problems and seeing excess battery use, then me doing a hard reset on mine just to stop BAP won't help me so I'm stuck with what I got.
I have asked others on this forum using W10 and Verizon to call Verizon to complain and ask them to add an option to uninstall or simply turn off BAP from your Verizon website account. They said they know of the problem with W10 users but they have no fix yet but said if enough people ask for the fix they may eventually make one. W10 finally has a BAP "uninstall" button under Apps but currently it is greyed out so can't be used... yet.
However, we all know Verizon is trying to get everyone to buy a new phone and drop W10 altogether so you would think Microsoft would make a fix to block BAP to keep their W10 users but is Microsoft really even in the Phone business anymore or just doing the W10-phone updates to make it look like they are even making an effort to compete? My OCD just won't let me move on although an Android phone is in my horizon especially since Microsoft is making Android Apps for everything from Office to Outlook to Onedrive to Onenote, everything Microsoft offers so again.... are they really even competing in the phone business anymore,