ipbno.tcif.telstra.com.au has no MX records.
Question and response
Question
dig ipbno.tcif.telstra.com.au. MX
Answer
The response has no answer records.
Authority
tcif.telstra.com.au. 3600 SOA adns01.bigpond.com. hostmaster.bigpond.com. 2021030321 43200 3600 2419200 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0