Command Code EBB Vortex Nine was a command code utilized to stand down the Mon Cala planetary defense services. During the invasion of Mon Cala, after learning that he was deceived by Ferren Barr into leading the monarchy into open rebellion against the Galactic Empire, King Lee-Char implemented Command Code EBB Vortex Nine to order all of his forces to stand down.
Admiral Raddus, upon receiving the order, believed that they could not give up on their efforts, and ignored the command, ordering the Mon Cala Mercantile Fleet to de-link and escape the world.