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

In Windows 10, the Calendar app is integrated and tries to take over calendar features. It produces a notification 15 minutes before an event, like this:

The 15 minute reminder is helpful, to go through the mental checklist of completing any last-minute preparations. Most of the time, that checklist happens quickly as everything's already complete, and I'd like the next reminder 10 minutes later, i.e. 5 minutes before the meeting, which is the get-up-and-go reminder. However, when I click in the area which says "5 minutes," as if to edit, I get a select-list with the following limited options:

How can I add a "10 minutes" option to this list?

Many of the events on my calendar are created by other people, so changing the default reminder time for calendar events I create will not be a good solution. I would like to add a custom time to the Snooze option in Windows 10, or be able to edit the value of an existing option.