We just wanted to inform you about upcoming changes to our firewall rules which may affect your applications.
While our documentation states that you should only use the server URL from the session, we have not previously disallowed other methods.
Having recently identified that some developers are performing requests to the wrong servers (main API server and/or different regional servers), causing multiple problems for our infrastructure, we have made the decision to restrict all requests that are going to the wrong server.
Please review your applications and make sure that you are only taking the server URL from the session (response from Authorise By Application call), and that the server URL is not hardcoded anywhere and is refreshed each time the session is recreated.
Starting next week we will slowdown all requests to the wrong servers.
The Linnworks Team