As far as I know the SuperO isn't a "space only" VT... Without the FAST pack it serves the same purpose within the atmosphere.
Well, obviously, without the packs, it is an ordinary VF, just unarmed.
I'm judging by the only time we ever really see it, which is in space, with packs on. It has been long assumed here on the boards (though there is no official canon source) that the VF-1D was for atmospheric training, whereas the VT-1 SuperO was for Space flight training using Fast Packs.
Anyway, I'm reading waaay too much into it!.
No in DYRL the VF-1D is replaced VT-1 in all applications.