You would like to know whether an earlier version of Lithium can upgrade directly to the latest version.
The latest general availability (GA) release is 19.10.
This release can be used to directly upgrade from all versions starting with Release 16.8. We do not foresee any challenges in upgrading from 16.8 to the current release. Release 16.8 to 19.10 will include OS kernel upgrade along with the Lithium Software packages and other related components.
All newer releases are constructed to maintain the features and functionality offered in the previous releases for ensuring backward compatibility. Release 19.10 is fully tested and already deployed successfully in production environments.
You can download the latest software by going to the NewNet Download Center