John Titor could come back to our time, and keep doing so infinitely.
The only difference would be the divergence value for each visit, which in effect would be slight changes in the worldlines, but overall the events would remain static to that individual worldline.
So.. as long as John were to choose to return to this time, he could follow the same steps he did previously, and come back to us under a slightly different divergence.
If ha arrived, and the event he came to manipulate was not in the state of existence it needed to be in, he would merely return to his time, and make the journey again, and again, until he came across the worldline that was closest to his initial visit.
