I have no idea. There's no obvious or common link between 7 15 and X-Men comics. Maybe it's a code or reference within a very niche aspect of X-Men lore that isn't widely known.
The X-Men Black comic was indeed cancelled. It could be due to a combination of factors such as changes in the comic market, reader preferences, or editorial directions within the publishing house.
The initial X-Men comic was 'The X-Men #1' in 1963. This comic kickstarted the popular series and laid the foundation for the X-Men universe we know today.
It depends on the specific comic storyline. Sometimes the X-Men are included in the Infinity War narrative, but not always. Their presence can vary based on the creative decisions of the writers and the overall plot direction.
The original X-Men comic was 'The X-Men #1', hitting the shelves in 1963. This comic marked the beginning of a long and popular series that has captured fans' imaginations ever since.