How do I add a custom snooze period to Windows Calendar notifications?

Solution 1:

Doesn't appear to be a way. The choices are mostly worthless for me.. Depending on circumstances, I may want to snooze until 10 mins before to days before a target date/time.

Solution 2:

The Windows 10 'Almars and Clock' app is very primitive and it does not have the feature setting you're requesting.