Purple alert is the highest NS alert and is one the NS hope will never be reached as the alert status basically means New Sparta is in imminent danger of being destroyed. Purple alert is more a final order to the NS than an alert status as it is assumed NS would cease to exist after it was raised. However there are plans for how the fight would continue and over the last few weeks NS have held a top secret exercise to practice for it.
Usually NS exercises are well publicised in advance and documented for propaganda reasons but the purple alert exercise (which has not been given a public name) was known only to a select few who took part in the series of scenarios and exercises. Most details of which are being kept under wraps.
It has been revealed however that dispersion of space assets was practiced, terrestrial forces went "underground" to prepare for a guerrilla action and various methods of communicating in the event of an NS meltdown were trialled including leaving messages in a newspaper personal advert column!
NS+ Commander Torus said that purple alert was unlikely to ever be needed but that NS needed to practice and prepare just in case. She said that some issues had come to light during the exercises and that procedures would be reviewed.