In a post on its official website, Niantic mentioned how it wanted to be "proactive" with the pricing notice and explained how it was "due to changes in App Store price tiers". Similar changes will also apparently be made on other mobile platforms.
Here's the full list of countries and regions affected (via Niantic's website):
- Territories that use the Euro currency
- South Korea
Niantic won't be taking "immediate action" in response to these changes, but will instead monitor the impact and then navigate these "changing conditions" globally.
If we hear any updates, we'll let you know.