Hi @opfoxtuck
Thanks for using Yoast SEO plugin and trying out the llms.txt feature.
The file will be be updated weekly by a scheduled action. However if you have created a new page or post and want to show it even before the weekly scheduled action, you can toggle off the llms.txt feature and re-enable it again after saving the settings page. Kindly ensure to clear the cache for the llms.txt to see the newly generated llms.txt having the newly published/updated page URL or else you can add llms.txt?nocache or any parameter to the end of the llms.txt file to view the new llms.txt file.
We have a detailed functional specification regarding the llms.txt generation at our developer portal.
Thanks. The information in your provided link is very useful.