Hi Cap,
I suppose Revell just delivered the typseven41 kits to "toys2day" (the boat is not listed on the Revell onlineshop) resp. the "toys" people ordered a limited edition because they have a eye on the plenty ebay auctions knowing that there is a huge demand (Quote: "The kit has been produced exclusively in an one-time-only edition for customers of toys2day").
The re-edition of the Prien boat is a riddle to me too, because the kit looks a little bit outdated and like a plaything, but maybe thats for what the Prien boat is good for: Beginners and retro-builder (people who assembled U 47 as a kid or teen).
Regards
falo