Zorin Group company has announced that they are working on a Direct Upgrade path (the
do-release-upgrade command) for a major Zorin OS release to the next major release. These are not 'point-releases' but are moving for example, from Zorin OS 15 to Zorin OS 16.
Currently, this is In Development. The process is not yet ready and has not been released nor announced by ZorinGroup.
Zorin OS operates with its own packages and its own repositories and performing steps to attempt to perform a Direct Upgrade prior to the infrastructure and release by Zorin Group will result in
Breaking your System.
This is an often asked about and much hoped for feature. Considering the ZorinGroups attention to detail, security and stability we can all only ask you to remain patient.
Please Do Not attempt to perform a Release Upgrade on Zorin OS until such time as the ZorinGroup Officially announces its availability.
We may not be able to help you to restore your system if it breaks here on the forum.
And you may lose valuable data, time and a non-achy head.