GuyPostington

    echo | openssl s_client -connect ${DOMAIN}:443 -servername ${DOMAIN} -verify_hostname ${DOMAIN} 2>/dev/null | openssl x590 -noout -startdate -enddate

   $ echo | openssl s_client -connect "www.certera.io":443 -servername "www.certera.io" -verify_hostname "www.certera.io" 2>/dev/null | openssl x509 -noout -issuer
   issuer=C = US, O = DigiCert Inc, OU = www.digicert.com, CN = DigiCert SHA2 High Assurance Server CA

   $ echo | openssl s_client -connect "certera.io":443 -servername "certera.io" -verify_hostname "certera.io" 2>/dev/null | openssl x509 -noout -issuer
   issuer=C = US, O = Let's Encrypt, CN = Let's Encrypt Authority X3