[quote name='jae23']Season 4 is going to be 18 episodes total, so they won't release a season 4 box set until all 18 episodes have aired.[/quote]
Wrong.
The next three seasons, including this one, are supposed to be 16 episodes each, for a total of 48. However, if the strike isn't settled soon, this season may only end up being 8 episodes as that's all they have filmed so far.