Restrict AWS security group Source IP address to Electric IMP only

Hi,
Does anyone know how to identify the IP address that Electric IMP HTTP push requests are made from? Essentially I have an Amazon instance and I want to amend the security group setting to only allow push requests coming from the IMP cloud. Is there a source IP address for the Electric IMP cloud?

Thanks in advance

No, because there are many servers and the IP addresses change during deploys (we fire up another farm and migrate things over, then kill the first farm).

You could always add a secret to the HTTP request code in the agent and check for it on your server?

ok thought so. Thanks for the confirmation!