We've heard about GF looking at old caverns in Europe, looking at prehistoric cave paintings and such. I believe south of France?
Then there's strange dex entries for Kabuto, stating a certain region has a living specimen of it--implying that there are members of the species that never went extinct or fossilized; mentions of Wailmer that use to be land-dwellers; Gible apparently comes from a region hotter than Alola and subsequently even hotter than Sinnoh, its debut generation, so Gible's line is not truly a Sinnoh native; the current Tyrantrum is supposedly an incomplete restored species from its fossil, and the dex further mentions it possibly had feathers.
We also know the Dream Park/Jurassic Park guy in Alola still hasn't completed it.
Perhaps we are going to a region that is further back in time, like prehistoric times. Where specifically, no idea.
