Rockhopper Exploration, searching for oil in the North Falkland Basin, has been re-assigned operation of the Ocean Guardian drill rig to start work on the Ernest prospect.The rig is on its way to licence PL024 where it will drill the 100%-owned Ernest 26/6-1 exploration well over 30 days.Once it's done, the rig will return to the company's Sea Lion 14/10-2 well to conduct tests on its recent oil discovery. Sea Lion is the first find and contingent oil resource in the North Falkland Basin.