We have some server upgrades/maintenance scheduled for Tuesday night between 7-8pm PST. We expect to be able to complete it without any downtime, but there is the possibility that there may be 10-15 minutes of reduced performance (slower page loads). We will make every effort to minimize the impact of this maintenance.
The time we have chosen is our slowest time of the day. We picked this to minimize impact. It is highly likely that nobody will even notice that we did anything. We just wanted to keep everyone informed.