Why is the XP tracks on the Rail Jack Playbook longer?

Hey so I recently downloaded the official rail jack playbook and wanted to use them in an upcoming campaign. However I noticed that the xp tracks were slightly different then the standard character sheets. They are split in the middle and there are more ticks total. I was wondering what the reasoning behind this was, because it’s really stumped me.

While trying to find an answer on the internet I did find this Reddit thread, but I don’t feel like it fully explained it to me, and we don’t have any sort of official explanation from John Harper. Also, they seemed to think that the XP tracks were shorter, which does make a bit more sense, but that wouldn’t explain the black line separating the top and bottom, and why it looks so different from other XP tracks.

Now I’m left with more questions, and I’m still very curious about it. Anybody have any thoughts?