Nintendo does maintenance all the time, it doesn't necessarily mean the Wii U's getting an update.
Then there will be another maintenance, and another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one, another one.