What will Niantic do with Spinda?

I guess making an Antarctica regional exclusive would be a good way to trap spoofers. 😋

Antarctica seems unlikely.
I've heard a theory that it could be a countdown to gen 4 release since they started with 8, which would coincide with day 0 being Eevee CD. That theory should be debunked or confirmed in just 3 hours.

Unnecessary regional. They should just be scattered everywhere. The design intent for Spinda is that all of their patterns vary.

Gen6 Vivillon will use this idea better with regional patterns.
https://bulbapedia.bulbagarden.net/wiki/Vivillon_(Pokémon)#Evolution

An interesting aspect of Vivillon would be that trading the base and middle evolutions would not count as a special trade, but the regional form of the final evolution should still be locked in based on where it was caught or the location of the egg it was hatched from. (Good use for friendship eggs.)