If the festival is taking Secure Online Screeners, the CATEGORY page will display a blue dot with a check mark next to "Submission Online". ALWAYS check the category page that YOU intend to apply under, as category rules, requirements, formats and deadlines often vary between categories.
"Secure Online Screener" will be listed in the preview format drop down, on your submission details page.
The option will also be displayed in the category details page of the festival listing, under "Submission Copy Formats".
You can also use the advance search option to search for festivals accepting Secure Online Screeners. The search engine can be accessed from the left-side navigation from your account homepage. Once in the search section, select advance search, scroll down the page and select "Can Be" from the "Preview Format" and "Secure Online Screener", and then hit the search button.
And finally, you will have the option on your submission confirmation page.