We currently 'scan' incoming email for spam, the system then sets the subject to say if it believes the message is spam and it can move messages to a spam folder. This is based on the 'Spamassassin' software. We are now trying out an additional spam scanner called Rspamd.
We will test this out through the following steps:
Customers may be interested in comparing the spam scores of their email and we welcome any feedback - email in to support. We'll update this post with the progress.
...A problem has been identified with the traffic shaping code in the latest FireBrick Software. A temporary solution by way of configuration change has been applied to our routers, and a software update will be applied in due course.