 Complete the following phrase:  In February 1941, Punjabi returned to Scapa Flow with the Flotilla, before undergoing a refit at Rosyth in MarchApril. The work included the fitting of a RAF ASV type radar outfit modified for shipborne use. At the end of May, she was part of the escort for capital ships of the Home Fleet hunting for the German battleship after the sinking of the battlecruiser . On 27 July, she and escorted the cruisers and to assess the potential of using Spitsbergen as a refuelling base for escorts used in the defence of 