The Deep Island server will soon[*] be updated from Debian Squeeze to Debian Wheezy. Hopefully, you will barely notice - just a few minutes downtime during the final reboot, maybe half an hour if the MySQL server update behaves weird. But if there are larger issues during the upgrade (and when upgrading the OS, you never know), the downtime may become longer. I will announce here when the update is done, so that you know when everything should be back to normal.
[*] I plan to do this somewhen this week - maybe tomorrow, or maybe during the week-end.