How does the Send Later check box function work in the invoice section?

This functionality lets you send invoices by bulk and at a later time, Joemeilak.

Once you choose this option, here's how you can send them:

1. Click Sales.
2. Go to the Invoices tab.
3. Select the invoices.
4. Click Batch actions, then select Send invoices.

I've got a reference about emailing or printing an invoice. 

If there's anything else we can do for you, please don't hesitate to get back to this thread.

I've selected to send 12 invoices later to the same customer.

When I process all 12 invoices, in the All Sales List will the invoices be sent out individually or batched as one pdf?

We’re pleased to have you here in the QuickBooks Community, @Ifasciano. Allow me to share what I know about sending multiple invoices.

 You can save time and email multiple invoices as a batch instead of one at a time.

Follow these steps to proceed:

1. Select the Sales menu, then navigate to the All Sales tab.
2. Look for the checkboxes for the transactions you want to email. You can also select the Filter drop-down and filter by transaction type, status, date, or customer.
3. Click Batch actions and then Send Transactions.
   
   

You can refer to this article if you want to learn more about how to Email or Print multiple invoices and sales forms.

Feel free to comment below if you have any other questions. Enjoy the rest of your week!