I've run in to what I think is a bug in DatePicker.
I live in the UK, so I currently am on UTC+1 (British Summer Time).
When I set a Date Picker's DateTimeZone property to DateTimeZone.Local, SelectedDate shows the same date, and Text() function converts this to a UTC time 1 hour compared to what it would be in my local time. All correct.
However, when I set its DateTimeZone property to DateTimeZone.UTC, SelectedDate shows a date one day before. Text() duly converts this to a time wrong by 23 hours.

Am I right in thinking this is indeed a bug?