I am genuinely conflicted. Emily and Laura have very real street cred when it comes to rumors, but they have couched their language as non-absolute on this topic, so their rumor doesn't definitely close the topic..
Meanwhile, everything Nintendo is doing screams that the game is a Launch Day title. The game has become synonymous with the Switch. It's ever-present as the face of the Switch's offerings in all marketing materials. And now, this latest happening reinforces the impression.
So I'm torn.
I will say this: if Nintendo reveals BotW to be a Launch Day title on the evening of January 12th and GameStop announces that preorders will begin on the morning of the 13th.. get ready for an overnight preorder camping trip! And bundle-up - it'll likely be cold outside!