Updated with what we plan to do with the Mirocards:
We will be running this giveaway as a 48 hours promotion.
This means that any one who purchased a set of PBT 02 or PBT 015 within the first 48 hours of GB will receive a corresponding Mirocard for their set. The two cards combine into one image so maybe you could consider getting both.
The cards will be shipped inside the Milkyway's packaging, so you wouldn't have to worry about receiving a separate package for the Mirocards.
These are the rarities for the Mirocards:
Holo Rarity - 95%
Designer Signature Holo Rarity - 5%