Thank you for the report.
It is normal when a TimeSlot has been selected the AppointmentsPanel to be redrawn. However, could you please share with us some more details about your application, so it takes so much memory - are you using custom styles/themes, are you using custom Slots, resources and everything that you find is essential for tracking down the source of the problem. Initially, if you are able to isolate the problem in a sample project and send it to us, we will be happy to research the issue further.
Looking forward to your reply.
the Telerik team
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