If paradox space is slowly being sucked into the black hole, can there still be more sessions in the future, since the incipisphere exists within paradox space?

Paradox Space and the Furthest Ring don’t exactly function in Euclidean Time/Space. It’s likely prior to the Breach, an Eternity had already happened. You could argue all SBURB Sessions have already happen, and will retroactively happen in the past of the Homestuck Ending. We also don’t know if the Black Hole’s gonna stop at any point. This is Hussie we’re talking about, who sewed the Universe back together with the cable of a fan once.