It has been this way since the "B" ships began last year.
Part of the factor of their reduced price is that they are unable to mount the perma camos from the standard versions, thus a part of why were sold at a lower price.
This will be the same with the other "B" ships that will be released for 2019.
I mentioned this on a thread earlier today too.
Fem,
You asked for the reason and I gave it to you.
Under the logic you suggest those who already have the Tirpitz shouldn't be able to purchase the Tirpitz B, but alas you can because they are "different" ships (not talking about gameplay etc). I cannot mount a ARP Camo on my regular Myoko - because again - Different.
Your example regarding the Montana is just not the same, yes, you can own multiple perma-camos for ships, and its up to you to determine if you want to purchase additional perma camos. However, expecting a camo that is designated for one ship to work on another one... yeah. That doesn't work.
I apologise that you do not like the manner in which we have gone forward like this, but from the beginning these ships were designated as separate ships from their non-"b" variants.
Fem,
Off Topic:
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