Calendar day start/end time not changing...

I don't know whether this is a bug in Calendar or I'm just missing something. I have my 'Day starts at' set to 8AM and 'Day ends at' set to 11PM in the preferences window, but the Calendar simply would not change and it's driving me crazy. I never had this problem with Mountain Lion, but since I updated to this new MacBook Pro with Mavericks it just wouldn't work.