Towards the end of 1916, before I left the Fleet, a system of "protected" sailings was therefore introduced.

In this system the Commander-in-Chief, Grand Fleet, fixed upon a number of alternative routes between Norway and the Shetland Islands, which were used by all vessels trading between Scandinavia and Allied countries.

The particular route in use at any given moment was patrolled by the local forces from the Orkneys and Shetlands, assisted when possible by small craft from the Grand Fleet.
The Admiral Commanding the Orkneys and Shetlands was placed in charge of the arrangements, which were carried out by the Senior Naval Officer at Lerwick, in the Shetland Islands.

At this period the intention was that the shipping from Norway should sail at dusk, reach a certain rendezvous at dawn, and thence be escorted to Lerwick.

The shipping from Lerwick sailed at dawn under protection, dispersed at dark, and reached the Norwegian coast at dawn.