Just in case anyone hasn't seen this... For information upgraded my VM to 10.12 last night and it updates, colleague upgraded his and it doesn't (both running Sophos 9.5.2)
Hopefully this will help people.
As per your query,Yes it will work on Sierra .
Still we have some issues regarding it as mentioned in article:
There have been some reports of failed Sophos updates on macOS 10.12 with SAV installed.
The only workaround is to rollback to a supported OS or uninstall SAV.
