Read again I did get the CS with only 2 total types of assignments completed. The CS triggered after completing the Flutter quest without doing more assignments. I had already previously zoned outside the city to do Erisa quest and didn't get CS for completing that.
The only possibility is that completing quests can help you trigger the CS somehow, either randomly or by total number of quests completed. We already know Flutter is not a prereq since someone said they hadn't completed it, but got CS.