I think I can answer that, Phantom.
The media VPs are HUGE. If you've ever looked inside, there are dozens of folders, tables, components, sounds, effects and all sorts of stuff.
Adding one ship to a mod is easy. Adding dozens of new ones, all with slight differences from the ones they're replacing, making sure that the tables are all still compatible and functional together, and making sure that whatever animations and effects play nice with whatever goes before is a huge task.
If the FSU project has already started this task, but they know that a few new models will be available very soon, wouldn't it make sense to wait until they're done so as to roll all the effort together? That way, they wouldn't need to start over and make a whole new VP release when Oddgrimm finishes all the Vasudan ships in like a month.
tl;dr - Releasing Media VPs is a massive task that's very different from just making a model and releasing it.
I for one am happy to trust the FSU Project's judgement, and really appreciate everything they do.