How do you handle blanket Purchase Orders

What is the best way to enter a blanket purchase order? I entered a PO with
12 monthly releases. I received a release and changed due dates on the
remaining releases to simulate how we are used to doing things. When I
reprinted the PO the original release still showed up even though the line
was closed and received.

Am I doing something wrong?

5.00.332

Mitchell Kirby
V. P. Manufacturing
Riten Industries, Inc.

800-338-0027, ext 210
800-338-0717 FAX