A week ago thanks to a question on Dynamics Community Forums (link) and to Daniel Cai that spotted the crm12 inside the url, I became aware that a new region for Dynamics 365/PowerApps (located in France) was introduced, however the SDK was not able to connect to this new region as it was not updated yet.

Yesterday the SDK Team released an update to several NuGet packages (link), from the changelog:
Added support for France and New US Geo's

Microsoft didn't update yet the official documentation page but you can check in the next days if you need the exact Discovery Url (especially for the new US region, for the France one you just need to use crm12)

Meanwhile I was testing the new Plugin Registration Tool, I noticed they also introduced a new region in China, strangely the changelog didn't mention this.

Hope it helps!