The Symantec Brightmail scheduled IT maintenance window for systems which provide rule updates, IP reputation, and URL reputation occurs twice weekly at the following times:
Effective the week of February 13, 2019, Symantec Brightmail's IT team is changing the scheduled weekly maintenance window.
The window is being moved to Tuesday: 8am - 1pm UTC and Thursday: 6pm - 11pm UTC instead of Monday: 10am - 3pm Pacific Time
Barring any emergency maintenance required, Symantec Brightmail's IT team may need to perform back-end infrastructure and/or database maintenance or upgrades during this weekly window which may result in no new antispam definitions (rulesets) being created or available for short periods within this time frame. Typical maintenance work lasts from 20 to 60 minutes. If such maintenance is required, your Brightmail Scanners/Servers will continue to scan messages with the existing antispam rulesets until the maintenance period is complete and new ruleset propagations commence. Symantec Brightmail does not consider these events as an outage unless new antispam rulesets become unavailable for more than 4 hours.
If you receive any server notifications during this timeframe for rulesets being too old or not updated, it is generally safe to ignore those warnings. We apologize for any inconvenience the maintenance or upgrades may cause.