#7 - Sept. 23, 2013, 10:51 p.m.
Paragon experience is only earned when you are playing a character who is max level. If you are level 60 and paragon 100, when the expansion launches you will continue earning paragon experience in the new system. Once you have the expansion enabled your experience earned will take you from level 60-70 at which point it will again be added to your paragon level instead of character level.