In November 2017 we launched the largest update ever for our Stratus theme that includes a long list of new features and improvements, the most important one being a brand new visual drag and drop builder.
Our original meta box page builder system worked very well, but now that Stratus had been available for 2 years a lot changed and the new system is a great improvement.
We wanted to deliver the best possible experience and didn't want to compromise on the features of the new version so it is a full rebuild, and as such there isn't a simple upgrade option from v2 to v3. It's essentially a new theme. So for all existing customers, you have the option to continue to use v2, or included for free - you can install v3 as a new theme and recreate your content in the new system.
If you choose to upgrade to v3, we recommend starting with a clean install on a new site.
There is separate documentation for the new version which is available here: http://themovation.helpscoutdocs.com
If you have any questions, please feel free to open a ticket here on the support system: https://themovation.ticksy.com/