upgrade path

What is the upgrade path?
we own a license for version Version : 5.5.0 and would like to upgrade to version 6 or a service desk that has the assetexplorer built in
Is assetexplorer going to be part of servicedesk + ?
can one upgrade version 5.50 to use asset explorer module?

btw: mail sent to support@assetexplorer.com
just bounces back