>>4059811 (pb)
Trying to forget that I ever did IT work.
Here are some basic explanations that may help you make connections.
MX records:
https://dnsdb.cit.cornell.edu/explain_mx.html
Amazon Web Services:
https://docs.aws.amazon.com/general/latest/gr/aws-ip-ranges.html
https://aws.amazon.com/
Hmm flipped..might be a good theory