[ckstuart]

I figured it out. I am using the calendar scheme I guess because I have the Calendar Integration turned on in settings. However, I also had the Show Alerts turned on under the Due Reminders settings. Apparently these conflict with each other and the local notification supersedes iOS calendar alarm.

After turning off the Show Alerts, I am now receiving notifications prior to the due time consistent with the Calendar Integration setting of "X minutes before" the due time.