AKA Solo Challenges - How many have been released yet?

I'm wondering how many Solo Challenges of the AKA promo have been released yet. The Solo Challenges menu (i.e. the overview where you can see the list of all available Challenges from different promos) shows me that I've completed 18 of 24 challenges.

Furthermore, when clicking on AKA the milestones bar shows 72 stars completed and that there are two more tiers to reach (82 and 96). I've collected all available stars from all visible challenges. 

Therefore I'd guess that there should be 24 challenges available. But:

I only see 18 challenges (12 in AKA week 1 and 6 in AKA week 2). Is there something missing? Or have these challenges not been released yet but will be released soon?