Does changing PO/ Req prior to PO Approval send another PO Approval Notification email

We have purchase requisitions (P4310) set with PO approval routes and all works as expected except for one feature: when a PO req is revised PRIOR to being approved, the approver receives another PO approval email notification.It was my understanding that changes to a PO or req only send another PO approval email notification to the approver AFTER the PO/Req has been approved based on P4310 processing options (Approval Tab). Our P4310 version is set to reroute a requisition through approval based on standard critical fields and this works as expected, I just thought that this processing option only referred