Though the MC80 Liberty was able to hold it's own against the ISD MK1, the introduction of the ISD MK2 proved to be problematic for the Rebels. The MC80B, 'Mon Remonda type' was still along way off from being developed. The Rebels needed a heavier cruiser in the mean time that could better counter the ISD MK2. The MC80 Liberty Star Cruiser would be used as a test bed and reconfigured into the MC80 Liberty Battle Cruiser. Rebel technicians replaced the troop carrying capacity and cargo holds with additional hangars space. This allowed the cruiser an extended fighter compliment to match that of the ISD's, Heavy concussion missile launchers were added to the wings, with some variants receiving prow mount proton launchers. Very few MC80 Liberty star cruisers would receive these upgrades as it was simply not practical to take such crucial ships from front line duties.
It could add some extra upgrades for the MC80 Liberty, the MC80D could add extra fighters, whilst the MC80E could add extra weapons. The research and production costs would be suitable more expensive.