Nintendo has now provided an update on the extended Super Mario Maker fix, issuing the following statement:
We are carrying out emergency maintenance to fix a bug that occurs in "Create" mode. During this time, Super Mario Maker's online services will be unavailable.
We are currently preparing a software update to fix this bug. The online service will be available again after the software update is distributed.
If you've been planning to play Super Mario Maker courses over the next couple of days you're out of luck. Our video man Alex was getting up to some shenanigans in the level creator when he realised all online aspects were down and, sure enough, there's a whopping period of downtime underway.
In total it'll be underway for 37.5 hours, with the maintenance taking down all network services in the game shortly before this article was published. That means no course browsing or playing online, and you can't even upload your own courses. You can still create and save courses offline, of course.
The downtime details are below.
Wednesday January 27 at 3:30am Pacific / 6:30am Eastern / 11:30am UK / 12:30am CET until Thursday January 28 5:00pm Pacific / 8pm Eastern / 1am UK (29th January) / 2am CET (29th January)
That's a substantial downtime window, and hopefully the work will actually be completed sooner. It seems unconventional for it to be down for that amount of time, so we'll follow up with Nintendo to try and find out more.