Ah, so this is why Dexter Morgan will be renewed and recharged when see him again in September:
Executive Producer Sara Colleton tells TV Guide the show wanted its main character to be in a "positive place" on season six. Therefore: "[We'll] jump ahead a year and find that Dexter has gotten his groove back. He's gotten over Rita and Lumen."
New showrunner Scott Buck previously said the new season would focus on a spiritual search for Dexter. Can Colleton expound on that tease?
"There are things in life that Dexter's dealing with and one of them is that Harrison is now two years old and he has to go to school," she says. "There are things that he has to start thinking about with his son, and he's been keenly aware of what it is that he doesn't want to pass on to Harrison, namely his Dark Passenger, but Dexter has no idea what it is that he does want to pass on."
In a few months, we'll find out what the killer decides.