Fresh remailer statistics are the most important aspect of using anonymous remailers. The network is constantly in flux. What worked yesterday may not work today--literally. It's the fresh statistics reports that keep the network humming. Test messages are constantly sent out by the stats sources and through these tests a good working knowledge of the network is established. This knowledge is valuable for only a short time. Tests are constantly in progress and the stats reports themselves are updated regularly through the day.
Auto-update
QS comes to you set to update stats before each send. This is a good policy, but if you use QS frequently during the day, you might wish to be bothered a bit less. Click Tools/Options/Mix to get to the mixmaster options. You can change the policy of update before each send, to once a day using the drop-down list provided. That daily update will occur just prior to a send operation.
It is also possible to turn off updates entirely. In the normal course of events you will never turn auto-updating off. Don't do it. If you are forced, sometime, to turn it off because you can't get a message out, it's extremely important you you solve the update problem and get updates turned back on ASAP.
Manual Update
To perform a manual stats update, at any time, open the Stats Manager (Tool/Stats manager...) and click the Update button. The pages will be downloaded and, when you click Ok to leave the dialog, they'll be saved to disk.