Thank you sober for what you said, honestly, for a great modder as yourself to say that to a new modder gives me inspiration.
After digging into the campaign files deeper, To me it kinda looks like Ubi ran out of time and didn't get to finish the campaign the way they had wanted.
Ie. All port traffic and u-boats (the two properties I have looked at thus far) are set to all exit the game 1945 12 31.