Resolved -
All affected messages have been released from the quarantine. The issue is now resolved.
Nov 18, 01:42 UTC
Investigating -
We discovered a problem with an update that was released on November 17 around 2:30 AM GMT that caused a high number of false positives. The update has been rolled back and we will be attempting to release the affected messages over the next few hours. However you may want to check your quarantine closely for any missed messages.
Nov 17, 22:29 UTC