There's a definite shared style, with the roughly triangular heads and the long modular bodies. I can see where the mistake would come from - asked to guess I'd put a good chunk of those ships in the original BSG.
My bad Capt. hehe I am trying to remember that ship or ships your talking about, but I don't put it past them to reuse older models in the 1st BSG. After all I for that one from Silent Running, and yes that was a great scifi movie. I loved that one too.