Supplier contacts don't receive any notification

Summary:

When we don't mention any supplier contact on PO and if we have multiple supplier contacts with user accounts do we receive any notifications if PO is sent for acknowledgement.

In my testing it is observed that only if we mention supplier contact on PO header it is sending notification to that particular contacts email but not any other contact of that supplier.

is it the expected functionality?

Content (please ensure you mask any confidential information):

When we don't mention any supplier contact on PO and if we have multiple supplier contacts with user accounts do we receive any notifications if PO is sent for acknowledgement.