Azure Upgrade Path

Newbie starting out with testing Big-IP on Azure. I used the base template and it loaded 12.1.1. I see in Github there are more templates for 13.x. However, I can't seem to get the templates to load into Azure correctly.

 

Is there an easier way to download an image and upgrade my current deployment? I think in System > Software Management there is a way to load an image. Is that anything helpful?

 

Thank you as i suspect it is a basic question.