The Rebel Assault Frigate comes in small numbers in the Rebel Alliance due to the great cost and time needed to modify a Dreadnaught into a Rebel Assault Frigate. Rebel technicians removed most of the superstructure (including docking bays) to increase fuel efficiency and sublight speed. Dorsal solar fins with banks of manoeuvring jets increased manoeuvrability and the speed of the Assault Frigate. Using large scale automation, the Rebels were able to reduce its crew needs of this vessel. This was done by retooling being-operated work stations to allow droid and computer controlled stations. Once all of the modifications were completed, the barest hint of the original structure of Dreadnaught remained. However, much internal space was lost, meaning the most of the Rebel Assault Frigate's troop capacity was lost with it and no starfighters could be carried.

    However, this four engine ship does has 20 umbilical docking fixtures scattered about the hull. A few of the docks can be used with standard transports, but the majority of them are designed for use by light freighters and starfighters. While these open docking fixtures expose these frigates to greater risk, the power and resource requirements are considerably lower, and ships still can be carried through hyperspace. Each Rebel Assault Frigate carries a Modified Assault Shuttle piggyback atop their superstructure. These vessels unfortunately played an important role for the Rebel Alliance in the Battle of Endor.