According to the GWX manual. several boats sailed in mid august so they could be in a position to blockade england if such orders ever came.
obviously German high command had plans in the works... so they sent out some "front line boats" well before any hostilities became official.
Just complete one patrol, dont sink anything (my opinion) come back and then launch out to sea on patrol #2... head for the western approaches and await things to get hot.
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