Rockstar itself had, at one point said Trevor, Michael and Franklin would be coming back in new content for the game but they haven’t made any other comments since that first announcement. In fact, at one point, execs from the company actually tried to claim that no such promise of story based DLC was actually made. Forbes points out the firm made some comments to an investor at an earnings call that were rather funny when you look at how hard Take Two’s Strauss H. Zelnick worked at pretending no story DLC promise was made.
After Zelnick claimed no comment’s like that were made, the company later backtracked and said that kind of info could only come from Rockstar. Which is why it’s so frustrating that Rockstar has been so quiet about about any kind of new content. At this point, we have to hope they’re going to give us some great big surprise at some point by announcing it out of the blue. The further we get away from the original release though, the less likely that seems.