Some New Super Mario Bros. U players seeing saves deleted following update?

Update 2: Bumped to the front page with the following from Andy:

“I think I might have figured out part of the problem. When I first got my Wii U going after the day 1 update I plugged in the external USB drive I had hoped to use to download digital titles. The first Nintendoland and NSMBU updates were downloaded and installed while the drive was plugged in. I didn’t think much of it at the time because they are disc titles for me, I didn’t figure any data would be getting sent anywhere but the system. After a few days I unplugged the external USB drive to save power. It was shortly after that I was alerted to two more game updates for NL and NSMBU respectively. It was after those updates that the save data vanished. If other users mention save data wipes it might be helpful to learn whether they were using disc-based titles or digital ones and if an external drive was plugged in at the time. I really hope this helps!”

Update: Austin is here to add that he just talked to someone on Miiverse who said that their ZombiU save was deleted after an update. The start of a pattern…? I hope not!

Nintendo Everything reader Andy Holland tells us that all of his New Super Mario Bros. U save data was wiped following an update ran by the game today.

Andy says two updates have been automatically applied for him thus far. The first did not cause any issues. The second one, however, did.

Andy has since contacted Nintendo. We’ll let you know about any major developments about the situation.

It’s possible that this is an isolated incident, so don’t freak out just yet!