We know GBX has announced they are hiring for BL3, and production on the game is yet to be started.
True right? Wrong. Production = coding, artist work, etc. Concept and story are things that could be done a long time ago. And i believe before Burch left, he already made a nice script of where BL3 will be heading next. Why i am saying this?
Tales from the Borderlands is part of the Borderlands universe. i.e. you make changes in that game and whatever appears next will inhert those very changes. If not, Pre-sequel would have Roland alive and kicking. And the reason Borderlands 2 has been wildly successful because it brings back memories and tells stories. Some of them that was not part of the game (like attack on new heaven, nisha killing brick's puppy, etc). Tales too use those very things (at least the NPC) to spice things up. If Borderlands 3 wants to follow the footsteps of BL2, it'll have to bring in some former NPCs. But BL3 can't happen before Tales, it'll end up being another pre-sequel. It has to be set after Tales. Now comes a few tricks.
Tales features quite a few classes and NPC from earlier Borderlands. Now according to me GBX will use Tales as a background story (like what the NPC did during Tales timeline) for BL3.
Now not all NPC will appear in BL3 but at least some "should" end up there. And i believe one of them will be Handsome Jack (or his AI hologram). I may be wrong but will have to keep an eye on the other episodes as i feel in typical GBX style (though made by Telltale games) will hide a lot of clues and easter eggs.