Send Emails Later Users can receive reminder emails many days after they fill a form.

I assume

That's correct and here's a guide: https://www.jotform.com/help/535-Utilizing-the-Send-Emails-Later-Function-of-the-Autoresponder-Emails

Example: If you set to 3 Days, the submitter will receive the autoresponder message 3 days after submitting the form. Each autoresponder is only sent once.