Hello @aaronvectorcare,
Thank you for posting here in the Community. Let me share some clarification about the invoices in QuickBooks Online.
I can see how beneficial being able to shut off the feature whenever needed. Currently, an option or ability to disable the invoice email is unavailable.
We continue to improve the product, and this preference might be available in the future. As we assess this, I recommend you visit our QuickBooks Blog to stay updated with all the changes that are being made.
For additional reference, you can use the following article to edit customer information, like changing the preferred delivery method in QuickBooks: Edit customer information.
Drop me a comment below if you have any other questions. I'll be more than happy to help. Wishing you a good one.