When you delete a single appointment from a recurring series, you are actually modifying the Master appointment, telling it that it should skip the date in the recurring series. That's why instead of the AppointmentDelete event, the AppointmentUpdate event is fired for the master appointment. This happens because by nature the recurring series is treated as one appointment, rather that a collection of appointments.
When you edit a single occurrence, you are creating an exception in the Master appointment. The result is a new appointment, which behaves as a separate one (that's why it's stored separately in the database). However, there is still a link between the exception and the master, and you can still modify the master from the exception. That's why the dialog appears. For instance, you can choose to select an exception, edit the series and click Reset Exceptions, to return the state to the initial one.
As for the question - "How am I supposed to handle the RecurrenceExceptionCreated event", it really depends on what you want to accomplish.
Hope this clarifies things a bit. If you have any specific questions or issues, we'll be happy to assist.
the Telerik team
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