I turned off "Single Surface" on an existing game, and I can still see all the other factories on the map interface. The tooltip suggests that I would not be able to see them if "single surface" was turned off. Does the setting not work on existing saves?
As a side note, I tried toggling this off because when I picked up a factory with bots inside, after the roboport lost power all the bots started heading to a different factory.
Edited to add : this is for Version 1.2.2
