What controls security of the Add New Class button on LM_DM_ACTIVITY_PG when accessing the page thro

We are upgrading from ELM 9.1 to 9.2.  During UAT, we noticed an issue when logged on as an administrator and navigating to Enterprise Learning > Catalog > Maintain Courses, pulling up a course, choosing the Delivery Method tab, clicking on Scheduled Classroom link, then clicking on Classes tab.  The list of classes is shown as normal with links to each class enabled, but the Add New Class button is display only.   When logged in as another admin, the Add New Class button is usable.   The only code I can find that enables/disables that button is in the Page Activate