Nobody can know for sure, but since both Pa800 and Pa2X has been very succesful in their main markets I doubt that Korg would change their high end arranger lineup in the near future. The Pa800 is the succesor of the also very succesful Pa80 which was produced in 7 years (2000-2006). Read more here:
http://www.korgpa.com/pa_root/en/extra/korgstory.html?en

Kind regards,
Tommy