I guess so.
There are just two types of assets in ED.
Persistent assets are the same everywhere. The exist on all platforms, in all modes, in all instances. The can neither be damaged nor destroid. They can just be altered via BGS/server tick.
Examples are stations, bases, megaships, planets/moons, navebeacons etc.
Local assets are just existing in your instance. They are created when you enter the instance, they cease to exist when the last cmdr leaves. These can be damaged and destroid but doing so has no effect on the other instances (other then bgs effects).
Examples are the ships that spawn around stations and bases, turrets on megaships, ships around navbeacons etc.
So if its persistent, then its persistent everywhere.
And regarding the one-per-instance-limit: I'd guess that means one actual, physical ship per normal-space instance. The carriers wont be present in sc, probably a poi that marks them. Just like you never have two starports in one instance, but several in the system.