IGN is reporting that cloud saves, which are a part of your Nintendo Switch Online subscription, will be saved for up to six months after a unsubscribe.
This means that if you do decide to unsubscribe from the service your saves will be saved for up to six months, which is apparently the same amount of time that Sony keeps your cloud saves for, which are a part of your PlayStation Plus subscription. This seems to be a change of heart from Nintendo, which is good news for Nintendo Switch owners.
Nintendo spokesperson speaking to IGN
If a Nintendo Switch Online membership expires, users won’t be able to access their Save Data Cloud backups. However, Nintendo will allow users who resubscribe within 180 days to access their previous Save Data Cloud backups
Well that is a lot better then what we first expected. Still we would prefer a way to local backup and import saves just to be sure. But it is a step in the good direction.