I have rewritten most of the xUPT code and i can't see how this could be possible now. Now, if you set to 1UPT, you can: - Place 4 land/sea military units, 4 air military units and 4 civilian units on a city tile (configurable via xml). - Place 1 land military unit, 1 air military unit and 1 civilian unit on a non-city tile (civilian limit is configurable via xml and can be uncapped). - Place 1 military ship and 1 civilian ship on a non-city tile. - If you produce an unit on a saturated city, it will be pushed in a free tile in the working city area, on the same continent. - Your city production will be canceled if the unit cannot be "pushed" in the working area (checks on military land and air and civilian units, not on ships, assuming there will always be space to put a ship). The production points are preserved. - The AI won't try to produce units if it can't place it. It has nothing to do with the era.