Which supplier contact is used for Email PO Communication when Supplier Site has Comm Method "Email

Summary:

Hello, as per Oracle docs, the Email address on PO header gets defaulted based on 1st: supplier contact and then supplier site. If there is a supplier who has more than 1 active contacts and those contacts belong to the same site address, then which contact will be selected to send PO Email communication?

I am not sure what are all various conditions around supplier contact selection and Email id selection (given on Site → Purchasing → Communication Email) to determine final email(s) to send to suppliers. If someone could please share the information, that will be very helpful.

Content (please ensure you mask any confidential information):