I believe there are some problems in the low power mechanism of IOS 14.3. My IPhone consumes much of battery even when I am sleeping everyday after upgrading to IOS 14.3... which means my alarm will not work if I didn't charge before going to bed. (sad)
Moreover, this problem force me to charge battery more frequently than before and this may shortage the life of my IPhone's battery... It is really URGENT PROBLEM!!. Please help!
Btw, the battery health is 90% currently.
Check the screen shots of battery usage here... - https://developer.apple.com/forums/content/attachment/54d1e957-9d95-4ab5-a838-4fe3140d27c3