iOS 12.1.4 battery drain

***Sorry, posted too soon. Trying again***

I have been part of the group that has been impacted by severe battery drain of ~1% every 5-15 seconds since updating to iOS 12.1.4.

I tested the options mentioned in this thread, and have found that the issue seems to be related to app data download connections and/or downloading new data on the device (downloading an app from the app store, opening an app that needs to fetch new data, fetching new content by pulling/swiping down to refresh within an app, background app refresh, etc). I have confirmed that this issue occurs in both native apps such as Mail, App Store, Podcasts, as well as 3rd party apps.

Close all apps this did nothing, and the battery continues to drain. If not immediately, on the next background app refresh.

Power cycle (restart) device you can see evidence of some people's theory that there may be something going on with battery percentage calculation. After the battery appears to have severely drained, a power cycle will show the battery percentage back closer to what you would expect the usage to be prior to the draining event. A power cycle will likely still result in the device attempting to fetch new data, and more often than not will resume battery drain

Turn off Fetch New Data (Settings > Passwords & Accounts > Fetch New Data > toggle Push to off) + Power cycle device battery continues to drain

Turn off Background App Refresh (Settings > General > Background App Refresh > Background App Refresh > Off) + Power cycle device At first I thought this solved the issue while I was at work for a few hours in the morning, but when I started actively using my phone a bit more the battery drain started again

Delete Skype for Business + Power cycle device This is where I discovered that the issue is not isolated to only 3rd party apps doing things in the background and adversely interacting with 12.1.4... I tried this because some people indicated that they thought it may be related to Skype. I thought this worked for a while as well, until I opened my native iPhone Podcasts app and it started downloading new podcasts. I then watched my battery start draining at a rate of 1% every 5 seconds (I could hear a clock ticking beside me and timed it)

Turn off Bluetooth + open an app and pull down to initiate data fetch/download connection battery continues to drain

Turn off Wi-Fi + open an app and pull down to initiate data fetch/download connection battery continues to drain

Turn on Airplane Mode + open an app and pull down to initiate data fetch/download connection oddly enough, this doesn't always seem to work in interrupting whatever process is trying to download new data, and in some of my testing the battery would continue to drain.

Turn on Low Power Mode (Settings > Battery > Low Power Mode) + open an app and pull down to initiate data fetch/download connection this has been the only solution that I have been able to use to consistently and reliably keep my battery from draining. If the device is plugged in and charging, it will turn Low Power Mode off once it reaches a certain percentage (89%? 90%?) so you'll need to turn it on again once you unplug

Switch to a different device with <iOS 12.1.4 I have a spare backup iPhone 6S which is still on iOS 12. Apple will not allow me to restore from backup without updating to iOS 12.1.4 so I did not complete this test

Factory reset + restore at this point I did not have the time nor the patience to attempt this, but I did see that it did not resolve the issue for another user

Again, it seems like the only way to reliably stop the battery drain is to break or interrupt whatever connection is trying fetch new data by turning on Low Power Mode. I do have a lot of apps on my phone that I use regularly, which I'm assuming is the reason I may be impacted more than others since there is a lot of background activity happening with each additional app.

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tl;dr the battery seems to drain significantly when downloading new data or making a connection to fetch new data (unclear which it is, specifically), and the only workaround that reliably helps is to turn on Low Power Mode (Settings > Battery > Low Power Mode)