At around 9:30am today we will be changing over to the new Exchange 2013 CAS Servers. The only thing this should effect is the look of webmail. It will now have the Exchange 2013 theme causing it to look different than it did in the past.
Update: Work complete as of 2:10PM.
We will be applying Exchange and Windows updates to the Exchange servers today starting at 9:30AM. Rolling reboots will occur. Some users may be momentarily disconnected and reconnected automatically as their mailbox fails over to other database servers. This process will continue throughout the morning, and into the afternoon until all servers are completed.