Inconsistencies with categories and breadcrumb navigaion

[KentT]

I've noticed some inconsistency in how multiple levels of categories are showing up in breadcrumbs.  My use of categories in Pages sometimes goes four levels deep, and three levels is common.  IPS seems to handle two levels of categories fine, but the third or fourth level sometimes "confuse" it.

Sometimes my  breadcrumbs display:as:

Home > Page (with database) > Cat Level 1 > Cat Level 2 > Cat Level 3 > Record 

While other times it is displayed as:

Home > Page (with database) > Cat Level 3 > Record

I can't determine why (from just using the GUI) that IPS is getting "confused"...