Configurable snooze time for scheduled tasks

[freedio]

Is there a simple way to add 5 minutes? Or could preferred snooze times be made configurable altogether? Many of the current options don't make no sense to me, or require extra effort to adjust to.

The reason is that when the notification for a task pops up, you can either start or snooze. But I don't want to start the meeting yet, because then time would start ticking. So I snooze and start on the next popup.

I use snoozing for planning: For an appointment at 16:00 I would like to set notification to 15:55 and then snooze for 5 minutes when the first notification pops up, so that I have a small, but decent lead time e. g. for regular online meetings. Currently 10' is the shortest snooze time, but that's actually too long, because I can do such a lot of things in 10' that the meeting all but drops off my radar.