Well according to the builder it's based on the FASA- Decker Class. An Excelsior/Ambassador Hybrid secondary hull, with Cheyenne nacelles, with a swept wing Galaxy look angled like a Sovie sketch in the TNG sketchbook so............ with "tweeking"
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It could easily be a pre-cursor to the Decker Class, or as the builder states
the Rigel class U.S.S. Liberator. That would place production anywhere from 2320-2350.