Use template sets to manage the way asset variations are published.
Create a template set to manage variations of a template. You can control which variation is used without changing the code on your site. This helps content managers rotate content without requiring IT to change a URL in the Web code.
Universal URLs are used to display the the template variation that appears on the page, based on the order they are listed in the set. The template at the top of the template set list is always published.
You can use any image preset URL from the list. Image preset URLs are like universal URLs. There can be more than one image preset URL.
You can move a template in the template order (for example, to the top of the list) by dragging it to its new location. Publish again to submit the new order.
You might need to clear the cache to see the changes. The change only appears on the website after the change has made its way through the cache cycle.