Today I got an alert stating that my firewall was not logging anymore, upon investigation it appears only my Fortigate logs are having their time stamps changed by 4 hours. This started happening after I applied the last update, though I made no changes to either system and previously this has been working for the last year properly.
As you can see in the attached picture I have the correct time stamp in the log, but graylog is not parsing that time correctly it appears. I have verified system time, graylog user time, and firewall time and they all match.
Here is what the logs look like before and after the update.