You are correct, the VisibleRangeChangedCommand is not called anymore unless a property that affects the visible range is changed. Those properties are ActiveViewDefinition, DayEndTime, DayStartTime,
FirstDayOfWeek, VisibleDays and CurrentDate.
Why do you need to refresh the data when the GroupFilter property is changed? Probably there is a better place to do that?
the Telerik team
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