AS per http://www.telerik.com/community/forums/silverlight/scheduleview/multiple-days-appointment-disappears-on-day-view.aspx

I am also getting multiple appointments in Week and Day view selection using Week/Day header double click. I have observed that VisibleRangeChangedCommand is going to fire twice.

First time it gives wrong date span and on second time it gives required date range. I am wondering why this command fires twice.
Please guide me for the same.

Hi Shimoli,

I wasn't able to reproduce the issue - the event is fired once as expected at our side. Can you confirm that you are using the latest release of RadControls? It will be really helpful if you could send us more details which will help us observe the issue. Thanks

Greetings,
Yana
the Telerik team