Complex sentence: In early May, the British Admiralty was on the alert that might attempt to break out into the North Atlantic; therefore, "Electra" was ordered to Scapa Flow for possible deployment against the Germans.
Split into simpler sentences: In early May, the British Admiralty was on the alert that might attempt to break out into the North Atlantic. As a consequence, "Electra" was ordered to Scapa Flow for possible deployment against the Germans.