Occasionally you may need to temporarily pause email delivery, due to a server decommissioning or a service migration, for example.
This can be easily done in the Control Panel within Security Settings>Spam and Malware Protection, by pecifying a non-existent server into the destination server field.
We recomend using 169.254.0.1, as it's a reserved public IP, which won't be reachable. We advise against using reserved private IP's like 192.168.0.1, 127.0.0.1, or others like 1.1.1.1.
Then we would spool your inbound traffic up to 7 rolling days, and the outbound traffic up to 24h, while you make the necessary updates on your end.
Once the final recipient server is up and running again, you could enter the correct (or even a new) destination server and we would begin delivering all traffic held in the queue to this host.