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No, this is not an über-Scagerrack -scenario...
By early 1915 it was clear that the war would be a drawn out effort and Hochseeflotte would remain significantly less powerful than combined Allied navies. As a result, the German Navy started the unrestricted U-boat campaign in the West.
But let's turn our attention towards East. In the Baltic, where Hochseeflotte could be deployed at ease, the German Navy was clearly superior to Imperial Russian Navy which had sensibly deployed itself to a kind of naval trench warfare behind coastal fortifications and extensive minefields.
Nevertheless, neither coastal fortifications or extensive minefields were impregnable. An amphibious campaign to wrestle control of Gulf of Riga and Åland isles in order to continue with additional operations towards Estonia and Finland, respectively, does not seem to be that inconceivable (and was naturally done against demoralized opposition in 1917-1918). An ASB dream case would naturally be the rush of Grand Fleet for rescue...