Sunday the 28th 8am CET(Central european time) is the 27th 11 pm PST (pacific standart time). It's the same time.
edit:
Suggestion: Remove the times from all announcements and add a link like the following to each newspost, should make it easier for everyone (maybe use a different service, though)
http://www.timeanddate.com/worldclock/fi…0&p1=1009&ah=12 (If you haven't disabled localization services the site should display you the event time in your current timezone.)