OK, makes sense. No indication that anything was wrong with the batteries before iOS 11, so why assume new batteries will help. It's strange though, because my

OK, makes sense. No indication that anything was wrong with the batteries before iOS 11, so why assume new batteries will help. It's strange though, because my experience, with a "new" replacement iPhone 6, is that iOS 11 works great for battery life. It's hard to understand, unless the replacement iPhone 6's they're making now have some difference compared to the old ones that has to do with battery life.