If you set automatic reminders, this will count by default for all your overdue invoices. You don't want these to be sent to all your customers if they happen to exceed the payment term? Don't worry. You still have the possibility to exclude certain customers from this.
You need to go to the company in your CRM and click on the three dots at the very top next to "Company Information".
Choose the option 'Invoicing preferences'. In the following pop-up you can choose whether you want this company to receive automatic reminders or not.