iSupplier Contact is getting the PO PDF FYI Email, though PO Notification Method is None

Scenario is -

Customer Expectation is that Email PO PDF Should Work based on Notification method chosen during PO Creation. This should valid for iSupplier Supplier User account also.

How to Reproduce -

Supplier has iSupplier Active User Account.

But, Supplier Site Notification Method is set as Null out of 3 Options (PRINT/FAX/EMAIL)

Now, Create a Contract Purchase Agreement in Buyer Work Center and Choose None in Agreement and it is approved.

Still, FYI Email Notification is going to Supplier User Account.

-----

After analysis of Workflow History for this PO 20050365 , we have found that

Does User want document e-mailed ? = No (As we have put None as communication method in Agreement).