So basically making separate packs for this one would be unfair for those who already bought it, so they are increasing the plat (it is actually cheaper to ge the full pack instead of buying 2100 plat from the store). Okay.
And I guess that for future heirloom packs you will be able to buy the skins separately "If we continue with this series, we are dedicated to ensuring all future Heirloom Collection releases have more purchase flexibility and reflect all feedback we received during this launch.".