I usually avoid saying anything on these threads where people complain about missing free stuff by a couple of days, but since you sound like a normal person just trying to figure out if there's any exception to what's said in the promotion, here's my take on this issue.
IMHO, companies that use this type of marketing campaigns to stimulate sales should expect the backlash of those "unlucky" customers that finally decided to buy those same products just days or a couple of weeks prior to the announcement of the promotion.
Do those users have the right to complain about not having free stuff too because of buying earlier than the ones driven by the promotion ? Well, honestly? No, they don't have that right. You should buy the products when you need them and/or when you can, so if you bought it 2 weeks earlier, heck, that's maybe because you needed them 2 weeks earlier, no? If not, why didn't you wait until you needed them ? ...and so on...
But, what's also tru is that these promotions have this type of backlash even if there's really no right for complaints (hey, that's life!) the truth is that these newer and even long time users/customers may feel a bit hurt for paying more or a lot more than those that just a couple of weeks later, decided to go along and take advantage of the promotion.
What's the solution to this? Do existing users or prospect buyers prefer companies stop doing these promotions? Of course not.
I guess there's 2 solutions the complement each other:
1) Users know these promotions happen, so they can wait for them when deciding to buy the products, because in a year, there's always at least one of these happening.
Can't wait a year, 6 months, 3 months for something like to to happen? Heck, then you're paying for that "urgency" so you shouldn't complain about missing the promo for a couple weeks.
2) Companies (i.e. Arturia) should set a standard grace period for these promos as a way to deal with these recent customers (or loyal users that happened to buy another product recently) avoiding at least some of these awkward (though not totally correct) feeling in some users of being cheated because they were unlucky in their decision of buying products that fall in this promo just weeks before. That's the "reward" they got for buying earlier and not later.
So... like some truly cool companies I'm fortunate to be a customer, Arturia should set, say... 2 weeks, 1 month, 1 week? Some kind of calendar "buffer" that would grant the same conditions in the promo to those recent buyers. There's really no way this kind of gesture can be as damaging financially as the promo itself, IMHO and heck, this marketing gesture would get even more karma points instead of this constant backlash of disgruntled buyers complaining for their unlucky decision of buying some days earlier.
and... that's my 0.02€ on this