The leak corroborates earlier reports that the Pro would have a third rear camera where its siblings would 'only' have two. Huawei has been teasing the P20's March 27th launch event with promises of seeing "mooore with AI," so there's a good chance the third camera is being used for object recognition. Also, it's notable that the P20 Lite is the only one of the bunch with its fingerprint reader on the back, though it's not yet clear why. It shouldn't be a slouch -- the Lite will reportedly carry a 5.8-inch screen, 4GB of RAM and 64GB of built-in storage.
While there are still some details up in the air (such as availability and price in key areas), the leak illustrates Huawei's strategy: like ASUS, it's gunning after Apple with all-screen phones in a wider price range. It's just a question of whether or not the P20 series has enough to offer besides eye-catching displays.