You can unlink an account via the website, once per year, even from a banned Switch. Any cloud saves up to the point of ban can be retrieved (assuming paid online), as can any legit purchase.
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Also for the record I have used checkpoint to move saves from banned>hacked non-banned>non hacked. Whilst connected to internet on non-banned/non hacked, and changing users of said saves. No bans. Saves were MHGU and Skyrim. Your mileage may vary, as ever only mess around if you're willing to take a ban.