52.213.117.160
ec2-52-213-117-160.eu-west-1.compute.amazonaws.com
52.51.219.255
ec2-52-51-219-255.eu-west-1.compute.amazonaws.com
54.171.104.148
ec2-54-171-104-148.eu-west-1.compute.amazonaws.com

eu-smtp-inbound-1.mimecast.com.
eu-smtp-inbound-2.mimecast.com.