Drag and Drop onto sfCalendar control

I have a windows form using a datagrid control and a sfCalendar control. I want to drag a job number from the datagrid onto a date on the calendar control and have code handle this occurrence in a separate fairly complex scheduling routine. How can I determine on which date the mouseup event occurs? I can trap for a mouseup event in the calendar control and I know if it is th result of a dragdrop event and I know the data to be dropped. I just can't see any way to identify the individual date on which the drop (or mouseup) occurs.

Forgot to mention - Visual Basic in Visual Studio 2019 community edition, Syncfusion v 17.1.0.38