Part of my design pattern is to use the Group API to group like-minded keys across caches (on the same cache manager) to the same segment.

With the introduction of NBST, though, the same group key used across different caches results in different ownership information. This is different behavior from 5.1.

(It looks like about a ~70% business logic degradation from 5.1 as well)

See the comments for ISPN-2291 for logs associated with such keys. (These keys use "edgeDeviceId=" as the group value.