You can do that with software
seems to think that yesterday wa a spring bank holiday in the UK.
If you look at Outlook you should be back at work today putting your feet up. However what Microsoft did not seem to know was that the UK Government put the Spring Bank Holiday back until next week, and added another day off for the Jubilee for good measure, to create a four-day weekend.
According to a blog post at Meteor IT, which also provides instructions on how to locate and correct the Outlook calendar, at least 23 countries are suffering from incorrect holiday dates. In fact the blog post was written in 2010 and Microsoft still has not gotten around to fixing its calander software on outlook.
There are instructions about how to fix them here