The “itemListElement” property contains posts/pages in that category, so as you add posts/pages to the category, they are added to the “itemListElement”, and when you remove them from the category, they are removed from the “itemListElement”.
Note that “itemListElement” is limited to 200 items by default. You can define the ‘WPSSO_SCHEMA_ITEMS_PER_LIST_MAX’ constant in your wp-config.php file if you require more.
BTW, since you are a Premium user, you can open a ticket at https://surniaulula.com/support/, since support in the community forums can take a few days between replies, where-as Premium service is much quicker. ??
BTW #2, WPSSO only clears its cache when required, so after installing the Premium versions, you may want to clear the cache under the SSO > Tools page.
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