 In January 2013 a contract for refit and recommission of the submarines "Carp" and "Kostroma" of Project 945 was signed with the Zvezdochka Shipyard, Severodvinsk.The necessary upgrade work was expected to take three years.It was expected that the submarines would be transferred to Zvezdochka before end of April 2013 and the overhaul of the submarines would begin in summer 2013.