Many satellite operators start their business with a single satellite. As their market increases, new birds are acquired, so that all aspects of their operative (hardware assets, staffing, ground software, the CONOPS itself) need to evolve with the growing fleet.GMV has scaled ground control segments from one to a dozen satellites and we are building a control system for a massive (900+ satellites) LEO fleet. In this paper we present our experience in operational scalability of satellite fleets, with special emphasis on practical advices and lessons learnt.