Steam database shows some changes to Cities: Skylines package that now mentions version 1.5. Changes were applied earlier today. Skylines subreddit has kind of exploded already, and people are asking about the coming features. Colossal Order’s response has obviously just been “We haven’t said anything” and “There is no update that I can discuss.”
We aren’t really sure if there will be an update in the coming weeks or if we have to wait until fall. We’ll see I guess!