An interesting footnote from the latest issue of the Eaglemoss Starships Collection, featuring the Cardassian Galor class ship:
The CG version of the Galor class...[has been] upgraded making it suitable for use in print and capable of being used for an HD broadcast
All of the appearances of the Galor in TNG used the physical studio model, along with the early appearances in DS9. The CG model was made later in DS9's run.
Two key points that I took away from this:
1) CBS still has original CG files for the Galor class, which lends me to believe the "reconstructing the CG from scratch" to not be as big of an issue. (That's not to say it's trivial, but it's much better than starting from scratch or having to negotiate with now defunct effects houses)
2) The HD upgrade has already been completed for the Galor model, despite it not being needed for TNG, since it used the studio model. Granted, they could have made the upgrades as a safety precaution just in case the model shots were unusable (as has been the case previously), but I personally think this is a good sign that they're looking forward to giving DS9 the full HD treatment.
That said, the other issue this month was the Jem'Hadar Battlecruiser. They briefly discussed the CG model, but nothing outside of the scope of the series itself. They also released the Defiant and the DS9 station previously, which, IIRC, got similar treatments to the Battlecruiser. The CG was discussed within the context of the show, but no hints as to the current state of the model as was done for the Galor.