Im playing a game right now and I started picking the Hittites; so I made a few outpost but I could not tell the difference between a normal outpost and a hittite outpost but I was like okay whatever maybe there needs to be an updated tooltip on it or something. Then I advanced Era and I picked the Mauryans and now I can't build Stupas. So that makes me wonder if perhaps theres a bug related to the culture unique district slow because of the automatic upgrade of the Hittites unique building. 

Any clues on this?