In trying to use Paged view with a volume of Christina History Magazine I opened up a floating window in paged view and obtained a pleasing three column layout.

After paging down a couple of times, the layout suddenly changed to two columns. Paging up did not cause the layout to return to three columns even at the same place I had previous had three:

I then looked for the information on the resource to show below and when I closed the information panel the above two column view reverted to three columns.
I have not seen this behavior in other resources so suspect it must have something to do with this resource. Here is the resource I was reading:
