Migrating from Central Email Gateway to Mailflow? Here are the documentations that will help:
Set up Sophos Mailflow (Note: Click on the "Existing user" link)
Fix conflicts with Microsoft 365 rules
Prevent duplicate scans
Testing and fixing Sophos Mailflow
If you have implemented Mailflow already, these are the expected entries within the 'Exchange admin center > Rules' page:
For the 'Exchange admin center > Connectors' page, these four entries should be there: