Now this is only my guess but here is why I think it is a certain person. I could be totally off and they could be pulling people in a certain direction... Nobody ever knows with this show, right!
As I was watching the show Talking Dead, it just seemed like some foreshadowing to me that Daryl is going to be the one getting the love of Lucille - Negan's barbed wire baseball bat.
They talked about Andrew Lincoln (plays Rick Grimes) trying to get Norman Reedus (Daryl Dixon) with a glitter bomb but it failed. So they showed this pic.
In the section where Jeffrey Dean Morgan who plays the new bad ass boss Negan and at they showed this photo at the end of his talk which has a look to it.
Austin Amelio who plays Dwight was on the Talking Dead show and he talked about taking Daryl's bike and also showed a clip of him on the bike dealing with some zombies on a highway.
There was also a comment read from the producer Scott Gimple that states that the narrative is going to go into a different trajectory for the characters away from the comic book pages. Which (if you don't know or not) has Glenn Rhee dying in the comic at the hands of Negan.
No wrong guesses since nobody will really know until the episode airs this fall. But I'm really starting to think it could be Daryl but throw out your speculations.