Despite being bankrupt, they still count the game rights among their assets, and though it's possible the rights to Freespace might come up sometime in the future, they will cost tens of thousands of dollars, and the original dev team has expressed serious interest in purchasing them.
In any case, we can assume that the first chapter would revolve around re-establishing contact with Sol. For gameplay purposes it would be probable that the contact would not be a peaceful one, since both FS1 and FS2 started the player off in an existing conflict before the Shivans arrived. We would hopefully find out why the Shivans did their thing at the end of FS2, perhaps find out what Bosch's fate was, and learn a little bit more about the Ancients. Really, it's up to the original writers to tell us what they had in mind, and they're guarding THOSE rights just in case.
Many campaigns hosted here on HLP (Like Inferno and Scroll) take place after the events of the main FS2 campaign, so you can play them and see how various community members are approaching it.