Thank you for writing.
I can confirm that GridViewDateTimeColumn
does not behave correctly in this case. I have added this as a bug report to our Public Issue Tracking System. Feel free to add your vote for it here: http://www.telerik.com/support/pits.aspx#/public/winforms/13641
However, I can provide you with a valid work around. Find attached a sample demo application.
I have updated your Telerik Points for this report.
I hope that you find this information useful. Please excuse us for the introduced inconvenience.
the Telerik team