Hi Corsair,
when you are back in your base, first select the "2. Flotilla" and then klick on the line (in top) "Apply for transfer". A "pop-up" with the message "New base: Wllhelmshaven" will appear - if not, the transfer failed.
Just one hint: do not upgrade you sub BEFORE your first patrol in your career. Otherwise you can get such problems.
Greetings
rowi58
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