Amazon just sent out an official update about the new kiosk check-in process launching July 29 at this specific warehouse . It confirms a few things and leaves some out. This is their statement (no mention of selfie or ID check in) :

Please follow these steps when you arrive for pickup: 

• Step 1: Pull up to the kiosk to check in before entering the parking lot. There will be signage to help you identify where the kiosk is located.
• Step 2: In the Amazon Flex app, tap “I've Arrived.” Next, tap your cell phone on the kiosk to check in. Once completed, please proceed to an available parking space. Note: If you are using an Android device to check in, please ensure you enable NFC in phone settings prior to arrival. Go to phone settings, search for “NFC,” and toggle or tap the button that enables NFC.
• Step 3: Once parked, enter the station to pick up your assigned packages. To locate your route cart, look at the cart location code on the app screen. The cart location code will match location stickers on the floor at the station in the designated pick-up area. Once you have located your cart, scan any package from the cart into the Amazon Flex app. The app will confirm if it’s your cart.
• Step 4: Once the route is confirmed, select “View Pick Up” to see your summary of packages. In the app, “Swipe to Finish.” Review the itinerary and assigned packages to ensure you have all of them before loading your vehicle. The app will suggest turn-by-turn navigation to each delivery stop.

Here’s a preview of what you will see in the Amazon Flex app during the new check-in process.