I need help with a site workflow based on the due date of tasks. The workflow would send a notification to the Assigned To person if a task is due soon or past due based on the due date
I believe you need to set up a "Call Web Service" and have it scheduled to run at a certain time. Where it would do some collection of data based on the current date and the variance due date. I know we have a few running but I don't have sufficient access to open those workflows without losing the login data for that action.
When using O365 Nintex, you can query the Assigned To and choose the property Email to save to a collection Variable. All you need to do in the query is specify a date from the due date to filter by. You can do that in the Add time to date action and use -10, or -3 to "add" days to the due date and get a new calculated date. That will be equivilent to 10 days before the due date.