Starbases beyond one are disabled is an ability for the Vasari Rebel's Star base, the Orkulus Star Base. The ability allows the Star base to phase jump. This ability is researched in the defense tree as Tier 8. The research technology is called Starbase Mobilization. Once researched, your Star Base(s) is (are) capable of phase jumping. The ability is hidden behind the Star base's upgrade management menu, so you don't see it, but it is a passive ability, so you only have to tell the base to jump to another planet like any regular unit in the game. You can only have one starbase per gravity well, but if you manage to get two in the same gravity well, one of them is disabled. It cannot launch strike craft, fire weapons and use abilities.
This ability is only in Rebellion.