Thank-you

That's what I thought.
However, I was able to create 1 Customer
For this 1 Customer I created 2 Accounts.
Then I create 1 Customer Site/Address for each Account.
.
Later I went back to see the Customer Site/Address and noticed that both Customer Sites had a BILL-TO and the value PRIMARY was assigned to this Customer Site.
.
The only thing that was strange about this is that when I tried to exit out of the 2nd Customer Site, I was getting an ERROR.
.
Anyway. thank-you for verifying.
I agree with your assessment.

Cheers :)
Charlie