Hi Bill,
Welcome to the AMP forum, nice to have you aboard.
I see exactly why this deck may be thought of as the later planked style. But the deck of the VIIC in the U 557 photo is definitely the early slotted deck. The deck pattern is typical of the pattern evidenced on the classic VIIC early slotted decks. Also, although it doesn't look like it, the spacers between the planks are actually at the same height level as the planks in this photo, thus making it the early slotted style.
Which boat are you building, by the way?
You'd be most welcome to post progress pics of your model.
Cheers,
Dougie