My understanding is that both bands will be involved in the tour, not BD and MK with MK's band, nor MK and BD with BD's band. It will be, I would hazard, the same as last time, in that both will play their own sets. I say this based on who told me what, way back last November, wehn this whole thing was first hatched.
The more interesting question, I would suggest, is whether this will be a genuine joint tour. Last time, it was a Bob which Mark was invited to join. This time, it is a tour that was initiated jointly. Maybe (just maybe) they will swap around who will provide the closing act. Time will tell.
That said, it has been intimated to me that it is Dylan touring team who have been making the basic plans for the tour. Tis is presumably because it's home territory for them and, because Dylan plays the USA more frequently than Mark, they would tend to seek to avoid visiting places too soon after the last time.
The other interesting things to watch out for are what sort of venues they play, in particular how large, and what sort of towns and cities. Dylan has a preference for going to new places on each successive tour (which is progressively more difficult as he continues to perform so many shows) but I suspect (and this is no more than a suspicion on my part) that this will be a fairly major event for both principals. Each will hope to feed off the other, as it were, in terms of attracting wider and larger audiences.
I wonder if the PR will dare talk about the giant of the Sixties combining with the giant of the Eighties or any such nonsense - actually, I think flim-flam would be a better noun, since both have produced such excellent work well beyond their initial success and prominence (and sometimes together, too).
Again, I await further news with both anticipation and inquisitiveness.