The time has changes from PST (pacific standard time) to PST (pacific daylight saving time)
What does it mean?
For Asian students (including Saudi Arabia): Classes will start one hour before until November 7, when the time will change back to PST).
For European student: Classes will start one hour before until March 28, when the time will change to daylight saving time in Europe as well. It will go back to standard time on October 31 and there will be confusion for a week, until November 7 when SL will change back to standard time too.
For Brazilian student: I'm really confused by Brazilian time. I hope you understand better than I do. Classes should be one hour earlier until your time changes (probably October 17).
For Egyptian students: Classes will start one hour before until April 30, when the time will change to daylight saving time in Egypt as well.
Anyway, don't trust me and check here: http://www.timeanddate.com/time/dst2010.html