Apple has moved the end call button to the lower middle area of the screen.
The button was previously present in the lower right area. The change was spotted since the first iOS 17 beta was released. It received a lot of backlash, hence, it is believed that Apple changed the position back to the middle.
Apart from this placement change, Apple has also moved the call screen controls a bit lower on the screen to make room for iOS 17’s new Contact Posters. These posters are designed to feature the faces of the people who are calling.
Apple will most likely reveal the new iPhone next month, and then make the iOS 17 update available to all eligible devices.