The time specified in the first screenshot is specifically when the execution of the deployment is to begin, where the time specified in the template is when to reboot after the execution of the deployment is finished, so they are two separate times.
For example, if you set the "On the next occurrence of specified time" in your template to be 3:00am, then you set your "Execute deployment package" time to 2:30am (maybe 1 hour after your scan starts or something), the deployment would begin execution at 2:30am. Then, if it was finished by 3:00am, it would reboot at that time. If it was not finished until after 3:00am, it would reboot the next day at 3:00am, since that would then be the next occurrence.
So, specifically, the "next occurrence" of a time is explicitly the next occurrence after the deployment task is completely finished. Does that help?