I have the same phone iPhone 7 Plus 100% battery health... updated to iOS 14.2 and it drained EVERY hour for 4 percent with no account logged in or no wifi connected. You might think that is not much but imagine putting your phone after sleeping at 11pm at 100%. The next morning you wake up to 72%. THAT is definitely a DRAIN.... I have another iPhone SE 1stGen thats updated to 14.2 that one has no issue at all... 100% at night and overnight it only dropped to 95% LOL

@Cramer92 no heck it doesnt work for me.,... my battery drain overnight standby