Visiting Grandpa
We know that John Titor claimed to be from the year 2036 and traveled to 1975 to obtain an IBM 5100 portable computer from his grandfather. This was supposed to be his sole mission before returning back to 2036. This is where it gets a little bit confusing, so stay with me. Titor’s grandfather wasn’t actually his grandfather, but his twin in this timeline. He made a promise to his twin brother (grandfather) that he would travel to the year 1998 to prepare the family [in this universe] for Y2K.
Source: Twitter
The first Art Bell fax talks about Y2K happening in his original world-line, but in the second one, he doesn’t mention it. It’s been theorized that John Titor sent the fax to Art Bell either when he first got there, or before he knew what the outcome of Y2K was in our timeline. He then spent two years with his family, preparing them for the Y2K event that never happened.