 Complete the following phrase:  By the end of August Westfalen and the rest of the High Seas Fleet had returned to their anchorages in the North Sea. The next operation conducted was a sweep into the North Sea on 1112 September, though it ended without any action. Another sortie followed on 2324 October during which the German fleet did not encounter any British forces. Another uneventful advance into the North Sea took place on 2122 April 1916. A bombardment mission followed two days later; Westfalen joined the battleship support for Hippers battlecruisers while they 