To reproduce this problem you have to follow the following steps:

1) Create a page hierarchy with at least 3 levels: Page 1 > Page 2 > Page 3
2) Move Page 1 and all its children to another space AND to another parent page
3) Goto Page 3 for example

The path shown by the breadcrumb should be:
Dashboard > New Space Home > New Parent > Page 1 > Page 2 > Page 3
but is displays:
Dashboard > New Space Home > Level 2 > New Parent > Level 3
Whatever the page you are browsing below Page 1, the breadcrumb is weird.