Busy cursor whilst custom sorting DataGridView C#

Question

Hello,
I am trying to show a busy cursor icon whilst programmatically sorting my datagridview for a column.
As I have a lot of data, it can take 10 seconds to sort, and I would like to show a busy cursor for this duration.
I can show the busy cursor icon when the user clicks on the column header cell (event).
However, I cant find a suitable event on which to return to the normal cursor.
Any ideas?
Thanks