Someone in this thread and another asked when the GE (Global Entry) scheduling availability is updated.

GE schedule IS updated in real-time. Fact.

Note: PHL automated voice greeting (also confirms above) says that they do not accept walk-ins and that you will be turned away. The CBP Officers that I had said they WILL take walk-ins. They had 4 officers rotating doing interviews. THEY ARE EXTREMELY FRIENDLY!!! I cannot stress that enough.

PHL GE Location:

Go to International Arrivals (Arrivals Rd Philadelphia, PA) Terminal A Parking garage. Do not pull into the short-term. Enter the garage. Drive to third floor of garage. When on the third floor make right turns and you will eventually see A West. There is an entry door on the side (where you will find at least one officer smoking at a time) which takes you straight to the CBP GE Entry office. There is a button outside of the GE door (which the door is loudly marked by a giant floor sign) to the left of the door that doesn't look much like a button at all. Press and they will answer you.