Harvey had initially hoped to return to game action this season. Instead, he will throw three more bullpen sessions before being shut down for the offseason.
While he won't be allowed to face batters or throw at 100 percent, Harvey - who has just been throwing fastballs - will be permitted to throw his curve, slider, and change during one of his final bullpen sessions.
According to Ackert, Harvey will continue the process when spring training begins in February. That will include facing batters and eventually appearing in games.
Harvey, 25, had Tommy John surgery last October.