Quote Originally Posted by Robby View Post
My mistake. I didn't buy them so I didn't pay much attention to the numbers. BUT

They may not have added a subtitle or changed the number, but they DID change the spines from white to black and made it veeeeery clear there was a break point, which was the change I had observed casually..

That's clearly marking the Shippuden split in all but name. And they also sell the big box set containing the first 27.

I suspect the only reason they didn't change the numbering is because it was selling like hotcakes at that point and they had just spent several months doing a speed up release to catch up to the japanese run.
I'm fairly sure Kishimoto himself split the series. If I remember correctly, at the end of the last Pre-Timeskip chapter, there's some text that says "End of Part 1". It's in the German version, so I assume it's also in the original. So it's not completely a Viz thing.