Being an Espada is a privilegium, but it also means you must maintain and follow the rules of Las Noches.
The Rules of Las Noches:
Rule 1: Please do not leave Hueco Mundo without telling the Espada Leader. This will result in punishment as demotion or removal of certain privilegiums.
Rule 2: Please do not use the Gran Rey Cero inside the dome of Las Noches.
Rule 3: Please refrain from bringing creatures of other races to Hueco Mundo without permission.
Rule 4: Espada ranked 5 and higher shall not release their Zanpakuto within the dome of Las Noches, unless it is crisis of course. The force unleashed is enough to demolish the fortress.
Rule 5: Caja del Negacion shall only be used if the Fraccion disobey you. If it is used in other ways, the leader of the Espada has the right to withdraw all Caja del Negacion you possess.
Rule 6: It would been appreciated if you followed the orders Espada ranked higher than you gave you.
Rule 7: If you spot a Former Espada, offer it a position in Las Noches. If it refuses, kill it please.
These rules will be lifted in times of crisis.