thank you for your reply, I can confirm, that the radgridview was empty on executing copy command. But I am absolutely sure, that I installed latest version availible, because the update was made on Sunday 28th of February.
I have checked the version control, the update was made from: 2015.3.1104.1050 to 2016.1.217.1050. If Telerik Control Panel by default installs the latest version, then it should be Q1 2016 SP1. So bug wasn't fixed after all.