Revealing mistake: The flags on Tipton hotel you see almost every episode never move; they're animated.
Revealing mistake: The top of the Tipton Hotel is animated. You can tell because in the opening of any episode showing the top of the hotel, there should be 3 visible peaks. You can see 2 peaks and if you look where the middle peak should be, you can see through the top of the hotel to the sky on the other side.
Revealing mistake: London's phone screen is visible, and it is shown that it is not a real digital phone.
Answer: The show never says.
Brad ★