I can't see why they would do anything else. Both Phil and Bob seem really happy and they are making great (even new!) music together. I'm pretty sure too that they have scheduled shows in October and the old contract ended in September.
I think Furthur is going to be around for a while! No expert, inside analysis here, just old fashioned deadhead intuition! You can feel the happiness from the band and crowd at the shows. No one wants to cut that short!