There are no particularly high notes in that studio version. And since the song was presumably written for her, there would be no reason to put in notes that are out of her range.
In general there are plenty of reasons why you might want to change a high note in a live performance. In the studio you can make as many attempts as you want to get a high note. If it's not working you can take a break and come back. And if it's still not working, modern studio technology can fake it so no-one will ever notice.
Live is a totally different story. The high note might came at the end of a two hour concert (on a gruelling two month tour) and you get exactly once chance to hit it. It can make sense to make it easier for yourself and sing a different note.