I was sending my gryphs off to Reserve when I noticed after the action was complete the game would return me to the second page of No Group (the gryphs were located in no group) instead of the first page like usual. 

Tested it in my Sacrifice tab with a uni as well, it's doing the same thing, redirecting me to the second page instead.

The game redirects you to the same page where a pet was before it was sent away. Were these two pets on the first or on the second pages of your No Group and Sacrifice tabs? If they were on the second pages, this is the expected behavior. If it was the first pages, then we'll need to do some deep debugging to reproduce this.

They were on the first page, I believe? Though the issue seems to have resolved itself.