They were saving them for challenges.
Which also means, that challenges were planned from the start, which in turn means, that the game wasn’t ready when it came out.
But that’s something we’ve known for a while now. Other things bug me, though:
- Why didn’t they tell us, that they were going to release skins together with challenge system? This would have made us happy, relieved, hyped up and we wouldn’t be suspecting early DLC with skins
- It seems, that these skins are available via commendation chests when you gather all the regular skins. If so, that’s a very very very bad news, since that devalues them completely. But that’s not accurate.
Overall I am glad, that these skins are finally in the game, and I think challenges is the perfect system for earning them. My only complain now, is that challenges are boring and are based on grind, not on skill. I would love something deed-like challenges with cool new modifiers, but I guess that’s too much to ask at current state of the game.
Good job, great skins 
