Talk:LR-GAT-X102 Regen Duel Gundam

How is it based on the Duels?
If both the GAT-X102 Duel and GAT-X1022 Blu Duel were prototype close combat suits, how is the Regen duel based on them and not the GAT-X103 Buster or GAT-X103AP Verde Buster]], since it is an artillery mobile suit?