Historically, Nintendo has announced things with that kind of lead time, but as of late, Nintendo has kept announcements much closer to the launch date. The Switch from announcement to launch ( Oct 20-March 3) is 134 days. Today, January 11th, we are 137 days away from Memorial Day (May 27), which is the unofficial start to Summer. The real start, June 21st, is a month after that.
My point is, things are way more open. Nintendo can announce and release the thing very quickly if they want to, and I find that much more likely than the drawn out reveals over 18 months that the Wii and Wii U got.
I would do the same thing I do with rare, single use items in video games (Think the Master Ball). I would save it indefinitely in case there is a time that I really need it in the future. I would die having never used it.