FYI I’ve had to introduce an automatic process for blocking users who violate the rate limits specified in the Terms & Conditions. This is because of a rogue app in circulation which is spamming the API.
Unfortunately, this might catch developers working on app development – when the real concern is apps published and distributed to multiple users.
If you find yourself blocked it should clear within 24 hours of your request rate dropping within the allowed rate. Apologies for any inconvenience.