Set Time Based Reminders for Specific Tasks


I want to know if there's any functionality for setting time-based reminders for specific tasks. For example, the other day I assigned myself a task to call my department's IT help desk. However, they were not available yet, and would not be until 8:30 AM.

How can I set a reminder for myself to call the IT help desk at 8:30 AM on the due date without creating a workflow for the entire sheet?

I understand there is the "Set a Reminder" function for each row, but there doesn't seem to be any functionality for setting the reminder for a specific time of day. It only allows you to set reminders for a specific date in general, not a specific time on that date.

I also know you can automate workflows to set reminders, but what I have in the following screenshot is the closest I can get to my desired functionality.

As you can see, it seems that using this workflow would send me a reminder at 9:00 AM for all tasks due today, when I only want a reminder for this one task. Also, in this workflow, I can only set reminders for the top of the hour (8:00 AM, 9:00 AM, etc), when ideally I would want a reminder for 8:30 AM.

I am new to Smartsheets, so it's very much possible I'm just missing this functionality somewhere, but setting task reminders for specific times is very important to me in how I manage my workflow, so any help on this would be greatly appreciated. Thanks!