We've found the new notification system is very customisable and a welcome change however it's usability for client administrators suffers a substantially due to the complexity of non-adhoc-on-event (scheduled) notifications.

We think it would be a great idea if the notification system made some assumptions and conveyed the windows in which it would trigger. What I mean by this is something similar to Amazon's event bridge rule scheduling UI. As you can see in the UI below when entering a cron time (similar to the time configured for the `process_scheduled_event_task` in Totara) it displays the next few times this rule will trigger.

Obviously this doesn't directly equate 1:1 to Totara as we'd need more context than just the task timing to calculate the notification windows.

With context:
My thought is that if the client admin is editing a notification template at a course level the UI queries the: course due date and the time that process_scheduled_event_task is setup to run at. Using this it could make an assumption that if the cron is running consistently the time the notification should be sent is XYZ.

Here is an example of adding a notification at a course level and brute forcing the window from Monday. Obviously this could be calculated in a much smarter manner than my brain allows at the current moment :). It would also have to be clear to the admin that the calculation is an assumption based on the cron running consistently and the scheduled task retaining it's current schedule.

Hopefully I haven't got anything above wrong, please let everyone know if you'd also like to see this feature.