Hey guys. A Polish store Muve.pl which is property of Cenega, the largest game distributor in Poland put Hearts of Iron IV D-Day edition up for pre-order yesterday. Since then, they were asked by Paradox to pull it and wait untill May 17th (which is when worldwide pre-orders will presumably go live). This is confirmed by Muve.pl itself on their Facebook event site about HoI4 release. Now, the D-Day edition they posted was a physical version (probably limited to few European countries, Poland included) and consisted of following:
DLC Package enhancing Polish gameplay: unique national focuses, tech trees and Polish military units
DLC Package: British tanks
DLC Package: American tanks
5 Collector's cards
CD with in-game music
Here's cover photo:
http://i.imgur.com/Jf5cL51.jpg
Now, the interesting part is, at the top of the cover photo there are listings of what can be found in the D-Day edition, in English on the left and in Polish on the right. Notice anything? The English side lacks any mention of DLC Package about Poland. Next, in the description of the game, before listing the content there's following line:
"Created specifically with Polish market in mind, the release issue of the game includes"
This could mean two things: the collector's cards and music CD alongside physical edition of the game are exclusive to Poland, while DLC is not or that the Polish DLC package is exclusive to Poland as well (and presumably avaliable for purchase on Steam later).
A cached version of the site can be found here (naturally in Polish, courtesy of klucz13 from this forum):
https://webcache.googleusercontent.com/search?q=cache:ApCjXkU5TKYJ:https://muve.pl/sklep/pc/strategia/hearts-of-iron-iv-d-day-edition-pc-pl,219473 &cd=1&hl=pl&ct=clnk&gl=dk
Facebook event page where they mention release stuff (again, in Polish of course):
https://web.facebook.com/events/1786470204922258/
That should give you guys some insight. I asked Muve.pl if the DLC is something special for Poland or if it will be avaliable for everyone and I'm currently awaiting for their reply. I'll inform you as soon as I get a reply from them (assuming I actually get one).