Subform Menu Question

I am developing a custom version of the AP16.1 Vendor Bank form called CZ16.1 to invoke a custom processflow trigger.

The problem is the AP10 Vendor form has a "Subforms" menu at the top of the screen. The second item in the menu list is "Vendor Bank". When clicked, the AP16.1 form appears. I don't want that to happen. I need my custom version (CZ16.1) to appear.

Any idea how to change which form appears? I looked through the AP10 compile listing...no references to AP16.1. I've searched through pgmdef, tokendef, laua, and Lawson Support.

Please help....Happy Holidays all!