I just saw that I have three apps with pending updates.
Nothing special in that. So I opened the App Store and clicked "update all" still nothing special.
But this time, I got this error message:
Account Not In This Store
Your account is not valid for use in the Taiwan store. You must switch to the U.S. store before purchasing.
Apparently I CAN get update notifications, but I can no longer get the updates. The message box gives me absolutely no hint about HOW I am supposed to switch to the U.S. store.
So now what can I do?