U6 MP2 includes a fix for this. Our tests so far have shown this gets rid of the annoying unwanted popup for this particular traffic event. Note that when upgrading from a version pre-RU6a, you need to patch rather than install the RU6 MP2 MSI over the old version.
Symantec Endpoint Protection firewall notifications are no longer displayed when notifications are disabled
Fix ID: 2038728
Symptom: When switching locations quickly, the application blocking notification will display, even though the notification should be suppressed by policy.
Solution: The location tracking code was modified to correctly suppress the notification.