This is not an acceptable solution.  I have done this now for several customers and now when I send a batch of invoices which includes one of these customers, QBO automatically sends it to my email, which means it is not flagged as still having to be sent, so now it gets missed, EVEN THOUGH I specifically do not check off the box where it says to keep the email address on file!!  Clearly it does remember it regardless and continue to use it for that customer, BUT it doesn't show in the customer's record so I can't even remove it now!!  So now all of my invoices for one of these customers will show as being sent when they are not.  So what on earth am I supposed to do now??  Where is this information being saved??  QBO sends invoices to me because somewhere my email is recorded for the customer but not on their record, so there is nothing to be removed.  Can someone tell me how to remove an email address that technically doesn't exist????