They won't. There's a massive number of people who will buy the package, just to get their hands on the ship (and people can always rationalise that all the goodies aren't 'useless', so they're worth the money). So, WG will feel vindicated and make a lot of money out of this.
Then, they'll pull the Tirpitz out of the shop, like they did with the Warspite, and only put it up (as a package), in the future, during e.g. holiday periods or similar.
After, say, 5 months of people in Tier 7-9 ships being rapid-fire sniped at or torped by Tirpitzes, there will be another massive number of people willing to buy it (because it's a good ship and clearly the fact that their WR is at 49% is due to the fact that they have only bad ships to play with, down in Tier 5).
TL;DR: I suspect the Tirpitz will only become available to buy on its own when the Kriegsmarine tech tree gets in the game, and people need a captain trainer ship. Until then, it's gonna be like the Warspite: always sold as part of a goodie package, to make the gods of WG some more money.
Which is all fine and dandy. They're a company. They're here to make money. If you don't like their methods, don't give them any money. If that means it's gonna take a year or so before you can play the Tirpitz, so be it. That's what I'm doing.