Unity Cloud Build can build projects created with most versions of the Unity Editor. Unity Cloud Build is usually available to new versions of the Unity Editor within 48 hours of the new version release.
Visit the Unity Cloud Build website’s guide to Supported Unity versions to see a full and up-to-date listing of all versions of Unity supported.
Is something described here not working as you expect it to? It might be a Known Issue. Please check with the Issue Tracker at issuetracker.unity3d.com.