Nintendo fans have long complained about the eShop policy regarding digital pre-orders. Up until now, everyone had to pay right away and there was no cancellation process in place either, barring very specific and exceptional circumstances.
Luckily, it seems like Nintendo has quietly made some changes. Pre-orders made through the eShop can now be canceled up until seven days ahead of release, which is also when billing will take place going forward.
Regarding Payment
The required funds will automatically be paid out of available funds at the time of payment. The expected payment date is no sooner than seven days before the product is released. (For bundles with different product release dates, payment will be processed no sooner than seven days before the first product release.)
Regarding Cancellation
You may cancel your pre‑orders up until time of payment.
You can check the product's expected payment date by selecting Shop Menu in your Nintendo Account settings then selecting Your Pre-orders, or via Your Pre‑orders under Account Information on Nintendo eShop on your device.
Payment will be processed based on the price when you pre‑ordered the product. Some discounts, such as an owner discount, may depend on holding a certain product at the time of payment. Depending on discounts and availability of special offers, canceling your pre-order may disrupt your ability to purchase or pre‑order the software at the same discounted price and/or your ability to receive special offers.
Do note that if you pre-ordered something on the eShop as recently as yesterday, the old rules will still apply.