The 25k rule would be for places only with friendly stations. They wouldn't be allowed to F1 ANYWHERE there isn't a friendly base in.
So say your Corsair, you cannot F1 in Texas, as there are NO corsair-friendly or Corsair-neutral stations in the system. If they were in say, Megellan, they could F1 in system, because of the Freeport there, but they cannot do it within 25k of Mactan.