I'm on 10.1 and I was able to download pokémon rumble world and pokémon shuffle after people in this thread said it wasn't working anymore.
Then after someone on 10.1.0-27U said they started getting the same error, I went to try to download Pokémon X latest game update (I don't even have pokémon X lol)
Worked fine.
If there's a fix maybe they're slowly rolling it out for eveyone? idk that wouldnt make sense.
just double checked my DNS Settings... and like a dumbfuck i still have the tubehax DNS in, set it back to google's IPv4 DNS (8.8.8.8/8.8.4.4) and it's working.
I've had TubeHax DNS on both primary DNS and secondary DNS and it worked fine for me.