Hi Paul,
Thank you for contacting Syncfusion Support.
No, it is not possible to select discontinuous set of dates in month view by holding the CTRL and mouse click action, as it may raise a difficulty and confusion on appointment creation through appointment window. The same problem raises in other views too in case of the different time range. Usually, we prefer and allow the multiple cell selection only for the purpose of appointment creation on the selected cells in either case of single or multiple dates (continuous date range) selected.
Note: The continuous set of multiple days can only be selected through the SHIFT and arrow key combinations, but not through the CTRL and mouse click combinations.
Regards,
Nevitha.