No expansion in phase three.
Eco Urban Lifestyle tech had an expansion. I think there was at least one on the map too. So, there were expansions in phase three. My guess is there will be in phase four also, just like in every phase prior.
NOW, for a question. What are the stats on this seed vault. I don't build crap for the fun of it. I see it gives almost a 3% chance of earning a "Resource" when aiding at level 10. What resources and how many? Do I have a 3% chance of earning 10 coin, 100 supply, 27 medals? What? Or, does it include FP, diamonds, etc, and if so, how many? A 3% chance at 1 diamond is very different from a 3% chance at 50 diamonds.
Also, do any GBs affect these resources (namely, the Chateau)?
The supplies just aren't worth it at all. I'm not sure what brilliant designer thought we needed another GB that gives off supplies. I think it's safe to say that most folks in Arctic are sitting on a few hundred million supplies already.