We’re constantly optimising Spoke based on ad performance so that only the best performing ad formats are used. As a result, the number of ad formats changes from time to time as new formats become available and we remove others no longer performing as well.
Spoke typically previews 7 or 16 ads depending on your campaign. However, most campaigns have typically have 20-40 ad variations. The ability to preview every single ad variation is planned to be released though.